Reference

Cannabis terms and definitions glossary

This glossary collects the strain-classification, growing, genetics, terpene, and breeder vocabulary that appears most frequently across cannabis seed catalogs and horticulture references. It currently runs to 134 terms across the alphabet and is written as descriptive definitions — what a term means, where it comes from, and how it is used in published source material — not as instructional advice for anyone considering cultivation, which is legal in some jurisdictions and not in others. Where a term has a longer reference treatment elsewhere on this site, the definition links across to the relevant strain library entry or grow guide. The glossary is maintained as a living reference and is updated when new vocabulary enters common breeder usage. Definitions are descriptive, not prescriptive, and effect-related vocabulary is framed by user reports rather than as predictive claims.

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A

Aeration: Aeration refers to the presence of oxygen in a growing medium or nutrient solution. Adequate aeration is documented as a precondition for healthy root respiration, and the term appears in references to soil porosity, perlite ratios, and air-stone use in hydroponic reservoirs.
Apical dominance: Apical dominance is the tendency of a cannabis plant's top growing tip to suppress the growth of lateral shoots below it. The trait is mediated by the hormone auxin, and most training techniques described in horticulture references — topping, fimming, LST — work by interrupting apical dominance.See also: Auxin
Autoflower: An autoflower is a cannabis plant that transitions from vegetative growth into flowering based on age rather than light cycle, a trait inherited from Cannabis ruderalis ancestry. Modern autoflower lines typically finish their full life cycle in eight to eleven weeks from seed and do not require a change in photoperiod to bloom.See also: Autoflower vs photoperiod
Auxin: Auxin is a class of plant hormones, principally indole-3-acetic acid (IAA), produced at growing tips and involved in cell elongation, apical dominance, and root initiation. Synthetic auxin analogues are the active component of most rooting hormones used in cannabis cloning.See also: Rooting hormone
Award: Award refers to a recognition given to a cultivar or breeder by an industry competition. The Cannabis Cup, Spannabis, and various regional cups are the most-cited examples; awards are typically referenced as marketing context in strain descriptions and are documented in breeder catalog histories.

B

Backcross: A backcross is a breeding step in which an offspring plant is crossed back to one of its parents (or a genetically near-identical clone). Breeders use backcrossing to reinforce a particular trait from the parent line and to stabilize a phenotype across a population.
Backflush: Backflush, in hydroponic systems, refers to reverse-direction water movement through a drip emitter or filter, used either as a cleaning step or as an unintended event that can carry root debris back into the reservoir. The term also appears in references to nutrient line maintenance.
Bract: A bract is a modified leaf structure that surrounds and supports a cannabis flower, often confused with the calyx in popular references. Bracts are densely covered in trichomes and form the visible bud surface that growers and breeders evaluate at harvest.
Brick weed: Brick weed is a term for cannabis flower that has been mechanically compressed into a dense block for transport, a practice associated historically with imported material. The compression damages trichomes and is documented as degrading both potency and terpene retention.
BX1 / BX2: BX1 and BX2 are generational labels for the first and second backcross. A BX1 is the first generation produced by crossing back to the original parent, and BX2 is the result of a second such cross, generally producing a population that more reliably expresses the recurrent parent's traits.
Breeder of record: Breeder of record refers to the breeder or seed company credited with the original release of a named cannabis cultivar. Provenance is treated as a meaningful detail because reused strain names sometimes appear from unrelated sources with different genetics.See also: Why the breeder of record matters

C

Calyx: A calyx is the small, often pear-shaped floral structure at the base of each flower cluster on a cannabis plant. Dense calyx development is a visual marker breeders and growers use to assess flower maturity and bud quality.
Cannabinoid: Cannabinoids are the family of chemical compounds — over a hundred have been identified — produced in the trichomes of cannabis plants. The most-cited members of the family include THC, CBD, CBG, CBC, and CBN, each profiled in laboratory testing of finished flower.
Cannabidiol: Cannabidiol is the full chemical name of the cannabinoid abbreviated CBD. It is a non-intoxicating compound produced in cannabis trichomes and is the second most-discussed cannabinoid after THC in breeder and laboratory documentation.
Canopy: The canopy is the upper surface formed by the topmost leaves and bud sites of a cannabis grow, considered collectively. Canopy uniformity is described in indoor horticulture references as a key variable for light distribution and overall yield.
CBC: CBC (cannabichromene) is a minor non-intoxicating cannabinoid produced in cannabis trichomes. It is typically present at lower concentrations than THC or CBD and appears in extended cannabinoid panels published by analytical laboratories.
CBD: CBD (cannabidiol) is a non-intoxicating cannabinoid produced in the trichomes of cannabis plants. CBD-dominant chemovars are bred for higher CBD-to-THC ratios and are commonly profiled in strain databases by their measured cannabinoid percentages.
CBG: CBG (cannabigerol) is a non-intoxicating cannabinoid often described as a chemical precursor to THC and CBD via its acidic form CBGA. CBG-dominant chemovars have been bred in recent years and are documented in newer cultivar releases.
CBN: CBN (cannabinol) is a cannabinoid formed largely through the oxidative degradation of THC over time. Elevated CBN values in laboratory testing are documented as an indicator of aged or improperly stored flower.
CFL: CFL (compact fluorescent lamp) is a category of lighting historically used for small-scale and seedling-stage cannabis cultivation. CFLs have largely been displaced by LED fixtures in modern documentation but still appear in low-budget or hobby-scale references.
Chemovar: A chemovar is a cannabis variety classified by its chemical profile rather than its visual or genetic lineage. The term is favored in research literature because two plants sharing a strain name can express very different cannabinoid and terpene levels.
Clone-only: A clone-only strain is a cultivar that circulates exclusively through vegetative cuttings rather than seed. Clone-only lines are not available as seed because the original breeder never produced a stable seed version, or because the genetics are held privately.
Co-dominant: Co-dominant, in cannabis pheno-hunt notation, describes a population in which two distinct phenotypes appear at roughly equal frequency and neither one is clearly dominant. The label appears in breeder documentation of unstable or recently created crosses.
Cola: A cola is a dense cluster of cannabis flowers formed at the top of a main stem or major branch. The largest cola, at the apex of the plant, is sometimes referred to as the apical cola and is the most visible reference point for flowering progress.
Crockett: Crockett refers to Crockett Family Farms, a California breeder whose Tangie and citrus-leaning genetics are widely documented in modern cultivar lineage records. The name is frequently cited in breeder credits for popular crosses descended from those lines.
Cure: Curing is the post-harvest process in which dried cannabis flowers are stored in sealed containers and periodically opened to allow controlled moisture and gas exchange. The curing window is typically described as two to eight weeks and is documented as influencing terpene retention and smoothness.See also: Drying and curing

D

Dab: Dab refers to a concentrated cannabis extract product — typically a wax, shatter, or rosin — described in product literature. The term is included here for vocabulary reference; concentrates are outside the scope of seed and cultivation coverage on this site.
Defoliation: Defoliation is the selective removal of fan leaves during the vegetative or early flowering stages of a cannabis plant. Documented goals include improving light penetration to lower bud sites and reducing humidity within the canopy.
DLI: DLI (daily light integral) is a measurement of the total photosynthetically active light a plant receives over a twenty-four-hour period, expressed in moles per square meter per day. DLI is calculated from PPFD and the daily photoperiod and is one of the standard reference metrics in published indoor lighting plans.See also: PPFD and DLI calculator
Dominant phenotype: The dominant phenotype is the expression pattern that appears most frequently across a population of seeds from a given cross. Breeders identify the dominant phenotype during pheno-hunts and often use it as the basis for future generations.
Dry trim: Dry trim is a post-harvest technique in which the plant is hung to dry with leaves still attached, and trimming is performed after the material has reached the target moisture level. The alternative is wet trim, performed immediately after cutting.
DWC (deep water culture): DWC, or deep water culture, is a hydroponic method in which plant roots are suspended directly into an aerated nutrient reservoir. DWC is documented as one of the faster-growth hydroponic formats but requires close monitoring of water temperature and dissolved oxygen.

E

EC (electrical conductivity): EC, or electrical conductivity, is a measurement of the dissolved-salt content of a nutrient solution, expressed in millisiemens per centimeter. EC is one of the standard metrics in published hydroponic and soilless feed schedules.See also: Nutrient reference
Effects: Effects, in strain documentation, refer to the qualitative experiences associated with a given cultivar as reported in aggregated user surveys and breeder marketing copy. Such effect descriptors are subjective and vary by individual; they are listed in strain references for descriptive context rather than as predictive claims.
Endocannabinoid: Endocannabinoids are signaling molecules produced inside the human body that bind to the same receptors as plant-derived cannabinoids. The term appears in scientific literature as part of the endocannabinoid system framework and is included here for vocabulary completeness.
Endotherm: Endotherm, in greenhouse and indoor cannabis cultivation, refers to a heat-releasing event or device. The term appears most often in references to nutrient solution warming, root-zone heaters, and the heat output of HID lighting systems.

F

F1 / F2 / F3 / F4 (filial generations): F1 through F4 are filial-generation labels describing the offspring of a documented cross. F1 is the first generation produced from two parent lines, F2 is the result of crossing two F1 siblings, and so on. Each successive filial generation is associated with increased genetic variability before stabilization is reached.
Fan: Fan, in indoor cultivation documentation, refers to a mechanical air-moving device used for canopy air circulation or for inline tent ventilation. The same word is also used in the unrelated term fan leaf, which describes the large photosynthetic leaves of the plant itself.See also: Fan leaf
Fan leaf: A fan leaf is the large, multi-fingered photosynthetic leaf of a cannabis plant, distinct from the smaller sugar leaves that grow from the flower clusters. Fan leaves are the primary site of light capture during vegetative and flowering growth.
Feminized seed: A feminized seed is a cannabis seed bred to produce almost exclusively female plants. Feminization is achieved by inducing a female plant to produce pollen, typically through a silver thiosulfate or colloidal silver protocol, and using that pollen to seed another female.
Fimming: Fimming is a training technique in which the apical growing tip of a cannabis plant is partially removed rather than fully cut, typically leaving roughly twenty percent of the tip intact. The technique is documented as producing four new main stems instead of the two that result from a clean topping cut.
Flower (stage): Flower, as a growth stage, is the reproductive phase in which a female cannabis plant produces the dense floral clusters that contain the cannabinoid-bearing trichomes. The flowering stage is triggered photoperiodically in non-autoflower lines and typically lasts seven to eleven weeks.See also: Flowering stage reference
Flush: Flush refers to the practice of irrigating cannabis plants with plain water in the final one to two weeks of flowering. The documented intent is to reduce residual nutrient salts in the plant tissue before harvest, though the practice is debated in agronomy literature.
Foxtail: Foxtailing is a flower-growth pattern in which newer calyxes stack vertically into long, tapering spires rather than forming dense rounded buds. The trait is documented as both a genetic tendency in certain cultivars and a stress response to excess heat or light intensity.
Fungus gnat: Fungus gnats are small flying insects whose larvae feed on organic matter and young roots in moist growing media. The pest is one of the most-referenced cannabis cultivation problems and is associated in published material with overwatering and uncured soils.

G

Genotype: Genotype is the underlying genetic identity of a cannabis plant, distinct from the phenotype, which is the visible expression of those genes under specific environmental conditions. Two plants from the same seed pack share the genotype but may show different phenotypes.
Geranyl pyrophosphate: Geranyl pyrophosphate (GPP) is a biochemical precursor from which the cannabinoids and many of the terpenes in cannabis are derived. The compound appears in scientific literature on cannabinoid biosynthesis and is included here for vocabulary completeness.
Germination: Germination is the process by which a dormant seed activates, cracks its shell, and extends a primary root. In cannabis seed lots the process is documented to take twenty-four to ninety-six hours under typical conditions.See also: How cannabis seed germination works
Grow medium: A grow medium is the substrate in which a cannabis plant's roots are anchored — most commonly soil, coco coir, peat-based mixes, rockwool, or an inert hydroponic substrate. Each medium has documented water-retention and aeration characteristics that influence irrigation frequency.

H

Hash plant: Hash plant refers to a family of indica-leaning cultivars descended from late-1980s breeding stock associated with resin-heavy, hashish-suited material. The name appears as both a stand-alone strain and as a lineage ancestor in many modern crosses.
Hempseed: Hempseed is the edible, low-cannabinoid seed of industrial hemp cultivars, used in food and oil production. The term is distinct from cannabis seed used for cultivation; hempseed sold for food is typically heat-treated and not viable for growing.
Hermaphrodite: A hermaphrodite, in cannabis breeding, is a plant that develops both male (pollen-producing) and female (flower-bearing) reproductive organs. Hermaphroditic expression is documented as a stress response and as an inherited trait in some lines, and is generally considered an unwanted outcome in seed production.
HID: HID (high-intensity discharge) is a category of grow lighting that includes HPS and metal halide fixtures. HID lamps were the dominant indoor cannabis lighting standard before LED fixtures, and they remain in published references for their high output and characteristic spectral profiles.See also: Lighting reference
HPS: HPS (high-pressure sodium) is a specific type of HID grow lamp, historically the standard for the flowering stage of indoor cannabis cultivation. HPS lamps produce a yellow-orange spectrum and large amounts of radiant heat, and they appear in most pre-LED grow documentation.
Hybrid: A hybrid is a cannabis cultivar produced by crossing parents from different lineage groups — most commonly indica and sativa, though hybrid is now the default categorization for the majority of modern strains. The term has lost some descriptive precision as nearly all commercial cultivars are hybridized.See also: Hybrid strains
Hydroponic: Hydroponic cultivation is the practice of growing cannabis with roots suspended in or irrigated by a nutrient solution rather than rooted in soil. Documented hydroponic formats include DWC, ebb-and-flow, drip, NFT, and aeroponics.See also: DWC

I

IBL (inbred line): An IBL, or inbred line, is a cannabis cultivar that has been bred for multiple generations toward genetic uniformity. IBLs are valued by breeders for their reliable expression and are commonly used as parent stock for new crosses.
Indica: Indica is a traditional classification for shorter, broader-leafed cannabis cultivars associated with the mountainous regions of Central Asia. Modern taxonomic and chemovar research has challenged the indica-versus-sativa split, but the label remains in widespread commercial use.See also: Indica strains
Inflorescence: An inflorescence is the botanical term for the flower-bearing portion of a plant. In cannabis, the inflorescence comprises the cluster of bracts, pistils, and trichome-bearing structures that growers refer to collectively as a bud or cola.

J

Jar cure: Jar curing is the most-documented curing method, in which dried flowers are placed in airtight glass jars and opened periodically (a practice called burping) to release accumulated moisture and gases. The process typically runs two to eight weeks and is described as the dominant variable in finished-flower quality.See also: The science of jar curing
Jiffy pellet: A Jiffy pellet is a compressed peat-and-mesh disc that expands when soaked in water and is used as a germination medium for cannabis seeds. The pellets are documented as a low-cost starter format and are typically transplanted whole into a larger grow medium once the seedling has rooted through.

K

Kief: Kief is the collected resin-gland material that separates from dried cannabis flower, typically through dry sifting over a mesh screen. The term, sometimes spelled keef, refers strictly to the loose powder; it is included here for vocabulary reference and is outside the scope of cultivation coverage.
Kush family: The Kush family is a lineage group descended from cultivars originating in the Hindu Kush mountain region. Kush genetics are documented as the basis for OG Kush, Hindu Kush, Bubba Kush, and a long list of derived crosses that dominate modern commercial strain catalogs.

L

Landrace: A landrace is a cannabis population that has adapted to a specific geographic region over many generations without modern breeder intervention. Landraces are treated as foundational genetics in cultivar lineage records and are referenced as the source material for nearly all contemporary hybrids.
Lateral branch: A lateral branch is a secondary branch growing outward from the main stem of a cannabis plant. Lateral branches develop bud sites of their own in flowering and are the primary targets of low-stress training and lollipopping techniques.
LECA: LECA (lightweight expanded clay aggregate) is a hydroponic substrate consisting of fired clay pellets. LECA is documented as inert, reusable, and well-aerated, and it appears in references to ebb-and-flow, drip, and net-pot DWC systems.
LED: LED, in cannabis horticulture, refers to light-emitting-diode grow lamps. LED fixtures have become the dominant published recommendation for indoor cultivation because of their efficiency and tunable spectral output.See also: Lighting reference
Lollipopping: Lollipopping is a defoliation technique in which the lower branches and small bud sites of a cannabis plant are removed during the transition into flowering, leaving the upper canopy with concentrated growth. The intent, as described in cultivation references, is to redirect energy into the larger top colas.
LST (low-stress training): Low-stress training is a canopy-management technique in which growing branches are gently bent and tied down to encourage a flatter, more even canopy. LST is documented as a way to expose more bud sites to direct light without the recovery time required by high-stress methods like topping.
Lumens: Lumens are a measurement of light output weighted to the sensitivity of the human eye. The metric is now considered deprecated in cannabis horticulture documentation, where PPFD and DLI have largely replaced it because plants respond to a different spectral band than human vision.See also: PPFD and DLI calculator

M

Macronutrient: Macronutrients are the primary mineral nutrients required by cannabis plants in the largest amounts — principally nitrogen, phosphorus, and potassium, with calcium, magnesium, and sulfur often grouped as secondary macronutrients. Feed schedules describe macronutrient ratios separately from micronutrients.See also: Nutrient reference
Mainlining: Mainlining is a structured training method in which a young cannabis plant is topped early and trained into a symmetrical manifold of equal-length main branches. The resulting plant produces a uniform set of top colas, and the technique is documented in long-cycle indoor grow plans.
Manifold: A manifold, in cannabis training, is the symmetrical branch structure produced by mainlining. The term describes the final stem geometry, with a single base node giving rise to a fixed, equal number of main growing branches.
Methyl jasmonate: Methyl jasmonate is a plant-derived signaling compound studied for its role in stress response and secondary metabolite production. It appears in academic literature on cannabis and is referenced occasionally as an experimental foliar input in agronomy research.
Mites: Mites — most commonly spider mites and broad mites — are microscopic arthropod pests that feed on cannabis leaf tissue. Mite infestation is one of the most-referenced indoor cultivation problems and is documented as difficult to eradicate once established.
Monocrop: A monocrop, in cannabis cultivation, refers to a grow consisting of a single cultivar rather than a mix. The term is used in commercial-scale documentation where uniform finishing time and canopy height are operationally valuable.
Mother plant: A mother plant is a vegetatively maintained cannabis plant kept in the vegetative stage to provide a continuous supply of clones. Mother plants are the basis for clone-only cultivar circulation and are typically held under twenty-four-hour or eighteen-six light cycles.
Mycorrhiza: Mycorrhizae are symbiotic fungi that colonize plant roots and extend the effective absorption surface through fine hyphal networks. Mycorrhizal inoculants are documented as a common soil amendment in organic cannabis cultivation literature.

N

Nitrogen: Nitrogen is the macronutrient consumed in the largest amounts during the vegetative stage of cannabis growth, where it supports leaf and stem development. Nitrogen deficiency is one of the most-illustrated leaf-symptom references in cultivation guides.See also: Nutrient reference
Node: A node is the point on a cannabis stem where leaves, branches, or pre-flowers emerge. Node count and internode spacing are documented as markers of plant maturity and as inputs to training-technique timing decisions.
NPK: NPK refers to the ratio of nitrogen (N), phosphorus (P), and potassium (K) in a fertilizer product. Cannabis feed schedules typically describe higher-nitrogen ratios for the vegetative stage and higher-phosphorus and -potassium ratios during flowering.See also: Nutrient reference

O

Off-gassing: Off-gassing, in a curing context, refers to the release of volatile compounds — residual chlorophyll byproducts, ammonia from incomplete dry, and aromatic terpenes — from cannabis flower stored in a sealed container. The term appears in references to the burping step of jar curing.
OG (Original Gangster): OG, originally short for Original Gangster, is a lineage label most associated with the OG Kush family of cultivars that emerged in 1990s California. The OG prefix appears in many derived strain names and is treated as a marketing and lineage marker rather than a strict genetic classification.
Organic: Organic, in cannabis cultivation, refers to a growing approach that relies on soil biology, composts, and naturally derived nutrient inputs rather than synthetic mineral fertilizers. The term is used descriptively in horticulture references and does not carry a formal certification meaning across all jurisdictions.
Outdoor: Outdoor refers to cannabis cultivation conducted in natural sunlight rather than under artificial lighting. Outdoor grows are documented as season-limited in most climates, with harvest windows tied to local daylength.See also: Indoor vs outdoor

P

pH meter: A pH meter is a handheld or in-line instrument that measures the acidity or alkalinity of a nutrient solution or substrate runoff. Cannabis feed schedules describe pH targets per growing medium, and the meter is documented as a standard piece of indoor cultivation equipment.
Pheno-hunt: A pheno-hunt is a deliberate process in which a breeder or grower germinates many seeds from a single cross and grows them out to identify the most desirable phenotypes. The selected phenotype is typically retained as a mother plant and used as the basis for future seed production or clone distribution.
Phenotype: Phenotype is the visible expression of a plant's genotype under a specific set of environmental conditions, including morphology, aroma, color, and growth pattern. Two plants from the same seed pack share the genotype but can present markedly different phenotypes.See also: Genotype
Photoperiod: Photoperiod, in cannabis cultivation, refers to the length of the daily light cycle. Non-autoflower cultivars are photoperiod-dependent and require a shift from longer to shorter days — commonly described as moving from eighteen-six to twelve-twelve indoors — to initiate flowering.
Pinching: Pinching is a low-impact training technique in which a stem is gently crushed between thumb and forefinger to weaken its vertical structure, slowing the growth of the pinched tip relative to surrounding branches. It is documented as a less invasive alternative to topping or supercropping.
Plant tissue culture: Plant tissue culture is a laboratory propagation method in which small pieces of plant tissue are grown on sterile nutrient media to produce clonal plantlets. The technique is documented in commercial cannabis as a means of preserving and multiplying clean genetic stock.
Pollen donor: A pollen donor is the male (or pollen-producing female, in feminized breeding) plant that supplies pollen for a deliberate cross. The pollen donor's traits contribute half the genetic material to each resulting seed.
Polyhybrid: A polyhybrid is a cannabis cultivar whose ancestry includes multiple distinct hybrid parents, as opposed to a simple two-line cross. Most modern commercial strains are polyhybrids, and the term appears in breeder lineage notes to indicate genetic complexity.
PPFD: PPFD (photosynthetic photon flux density) is a measurement of the photosynthetically active light striking a surface, expressed in micromoles per square meter per second. PPFD has largely replaced lumens and wattage as the published intensity reference in indoor cannabis horticulture.See also: PPFD and DLI calculator
Pre-flower: Pre-flowers are the small reproductive structures that appear at the nodes of a cannabis plant before the main flowering stretch, and they are the earliest visible indicator of plant sex. Identifying pre-flowers is documented as the standard method for separating males in a regular-seed grow.
Propagation: Propagation, in cannabis horticulture, is the production of new plants from either seed or vegetative cuttings. The term covers germination, cloning, and tissue culture, and it appears as an umbrella heading in most published cultivation references.

R

Regular seed: A regular seed is a non-feminized cannabis seed that may produce either a male or a female plant at roughly equal odds. Regular seeds are the format most commonly used in breeding programs, where male plants are needed for pollen production.
Reservoir: A reservoir, in hydroponic cannabis cultivation, is the container that holds the recirculating nutrient solution. Reservoir temperature, dissolved oxygen, and pH are documented as the three most-monitored variables in DWC and recirculating drip systems.
Resin: Resin is the sticky, aromatic exudate produced by the trichomes on cannabis flowers and surrounding leaf material. Resin contains the cannabinoids and terpenes profiled in laboratory testing and is the basis for most concentrated cannabis products.
Rockwool: Rockwool is an inert fibrous substrate produced from spun mineral rock, used as a seedling and hydroponic growing medium. It is documented for its strong water-retention and root-aeration characteristics, with pH conditioning required before first use.
Rooting hormone: Rooting hormone is a preparation, typically a gel or powder containing a synthetic auxin analogue, applied to the cut end of a cannabis cutting before insertion into a propagation medium. The product is documented as accelerating root initiation in cloning.
Ruderalis: Cannabis ruderalis is a wild-growing cannabis subspecies native to parts of Russia, Central Asia, and Eastern Europe. Ruderalis is the source of the autoflowering trait and contributes the photoperiod-independent flowering behavior present in modern autoflower lines.
Runoff: Runoff is the nutrient solution that drains out of the bottom of a container after watering. Measuring runoff EC and pH is documented in cultivation references as the standard method for monitoring root-zone conditions in soil and soilless grows.

S

Sativa: Sativa is a traditional classification for taller, narrower-leafed cannabis cultivars associated with equatorial regions. As with indica, the sativa label persists in commercial use even though chemovar analysis has shown that the cultivar-level chemical profile is a more accurate descriptor.See also: Sativa strains
SCROG (screen of green): SCROG, or screen of green, is a canopy-management technique in which a horizontal screen is placed above the plants and growing branches are woven through its squares. The intent is to create a uniform canopy at a fixed distance from the light source.
Seedfinder: Seedfinder refers to community-maintained strain databases that catalog cultivar lineages, breeder credits, and user reports. The most-cited resource of this kind is the seedfinder.eu project, frequently referenced as a lineage source in published strain documentation.
S1 / S2 (self-pollination): S1 and S2 are labels for the first and second generations produced through self-pollination — a feminized-breeding technique in which a single female plant is used to fertilize itself. S1 seeds carry only the genetic material of the original mother.
SOG (sea of green): SOG, or sea of green, is a cultivation method in which a large number of small cannabis plants are flipped to flower very early in their vegetative cycle. The technique is documented as producing a flat canopy of single-cola plants and shorter total cycle times.
Soil amendment: A soil amendment is a substance added to a growing medium to improve its physical or biological properties — examples include perlite for aeration, compost for organic matter, and mycorrhizal inoculants for root symbiosis. Amendments are mixed into the base soil before planting in most published recipes.
Solventless: Solventless, in cannabis processing terminology, describes extracts produced without chemical solvents — typically by physical separation methods such as ice-water hash or rosin pressing. The term is included for vocabulary completeness; processing is outside the scope of seed and cultivation coverage.
Stomata: Stomata are the microscopic pores on the underside of plant leaves through which gas exchange and water vapor release occur. Stomatal behavior is the physiological basis for the vapor pressure deficit (VPD) target ranges used in indoor environmental control.See also: VPD calculator
Stretch: Stretch refers to the rapid vertical growth that cannabis plants undergo during the first two to three weeks of flowering. Stretch ratios vary by genetics and are commonly documented in breeder notes as a multiple of the plant's pre-flower height.
Substrate: Substrate is the broader term for any growing medium in which cannabis roots are established — soil, coco coir, rockwool, peat mixes, LECA, or other materials. Substrate properties determine water retention, aeration, and irrigation frequency.
Sucker: A sucker, in cannabis training vocabulary, is a small lower branch that is unlikely to produce significant bud and is typically removed during lollipopping. The term is borrowed from broader horticultural usage and appears in lower-canopy management references.
Sugar leaf: A sugar leaf is one of the smaller leaves that grow directly out of the flower clusters of a cannabis plant. Sugar leaves are typically heavily coated in trichomes, which gives them the appearance from which the name derives.
Supercropping: Supercropping is a high-stress training technique in which a section of stem is gently pinched and bent until the inner fibers crush but the outer skin remains intact. The plant repairs the damage with a thicker knuckle and typically grows back with increased branch strength.

T

Taproot: The taproot is the first root extended by a germinating cannabis seed, also called the radicle. A visible taproot of two to five millimeters is the standard reference point for transferring a germinated seed into a growing medium.
Terminal bud: The terminal bud is the apical growing point at the top of a main stem, the site at which apical-dominance hormones concentrate. Topping and fimming techniques are documented as direct manipulations of the terminal bud.
Terpene: Terpenes are the aromatic organic compounds produced in cannabis trichomes alongside the cannabinoids. Terpene profiles are documented in laboratory testing and are the basis for the characteristic scents associated with different cultivars.See also: Cannabis terpene primer
Thrip: Thrips are slender, sap-feeding insects that damage cannabis leaves by puncturing cell walls and leaving silvery feeding scars. The pest is one of the most-illustrated infestation references in indoor cultivation literature.
Top dressing: Top dressing is the practice of applying dry amendments — composts, mineral inputs, or organic fertilizers — to the surface of a cannabis plant's growing medium. The amendments break down into the root zone over subsequent waterings and are documented as a slow-release feeding method.
Topping: Topping is a high-stress training technique in which the apical (top) growing tip of a cannabis plant is cut off. The plant typically responds by producing two new main stems from the node below the cut, encouraging a bushier structure.
Tricalcium phosphate: Tricalcium phosphate is a calcium-and-phosphorus mineral compound used as a slow-release amendment in organic cannabis soil mixes. It appears in published recipes alongside other rock-phosphate sources and is referenced in long-term flowering nutrient strategies.
Trichome: Trichomes are the microscopic, resin-producing glands that cover the flowers and surrounding leaf material of mature cannabis plants. Trichome head color — from clear to cloudy to amber — is the visual reference most commonly used to assess harvest timing.See also: Harvest timing and trichomes

U

Underwatering: Underwatering is a condition in which a cannabis plant receives insufficient water for its root mass and environment, producing limp, drooping leaves and slowed growth. The symptom is documented as one of the most-frequently confused diagnoses, since overwatered plants can present similar leaf behavior.
Upcanning: Upcanning, also written up-potting, is the transfer of a cannabis plant from a smaller container into a larger one as the root system fills out. The practice is documented as a way to manage root-zone health without forcing an oversized container on a small plant.

V

Vegetative: The vegetative stage is the growth phase between seedling and flowering, during which a cannabis plant develops its stem, branch, and leaf structure but does not yet produce flowers. Vegetative growth is typically held under eighteen-hour or longer daily light cycles indoors.See also: Vegetative stage reference
VPD (vapor pressure deficit): VPD, or vapor pressure deficit, is a calculated measurement combining temperature and relative humidity that describes the drying pressure exerted on a plant's leaves. VPD targets are documented per growth stage and are widely used in indoor environmental controllers.See also: VPD calculator

W

Watering: Watering, in cannabis cultivation, refers to the routine of supplying water to the root zone. Documented best practice references include watering to a small percentage of runoff in soil and timing irrigation to the weight or moisture content of the container rather than a fixed schedule.
Wattage: Wattage is a measurement of the electrical power drawn by a grow light, expressed in watts. Wattage is documented as a useful input for power-cost calculations but has been displaced as an intensity reference by PPFD and DLI in modern lighting documentation.
Wet trim: Wet trim is a post-harvest technique in which fan and sugar leaves are removed from the cannabis plant immediately after cutting, while the plant material is still fresh. The alternative, dry trim, is performed after the material has dried.See also: Dry trim
Wick system: A wick system is a passive hydroponic format in which a fabric or rope wick draws nutrient solution from a reservoir up into the growing medium via capillary action. The format is documented as low-cost and low-maintenance but limited to smaller plants and lighter feed loads.

Y

Yeast: Yeast contamination on drying or curing cannabis flower is documented as a common storage mistake, typically resulting from sealing material before it has reached a stable moisture content. The term is included here for vocabulary reference in post-harvest discussions.
Yield: Yield is the dried-flower weight produced by a cannabis plant, typically expressed per plant or per square meter of canopy. Breeder-published yield figures are documented under controlled conditions and are treated as approximate references rather than guarantees.