The plant and its names25 terms
- Strain
- A name under which cannabis plants or flower are grown and sold, such as Blue Dream. In cannabis, “strain” is used loosely for what botanists call a cultivar, and plants sold under one name are not always genetically alike.
- Cultivar
- A cultivated variety: a group of plants selected for particular characteristics that stay distinct, uniform and stable when the plants are propagated in the right way. The term and its naming rules come from the International Code of Nomenclature for Cultivated Plants.
- Chemovar
- A chemical variety: plants grouped by their chemical make-up, such as their cannabinoid and terpene profile, rather than by name or appearance. On this site, a strain’s chemovar is its most common terpene pattern in lab tests.
- Chemotype
- A class based on the balance of THC and CBD: THC-dominant, balanced or CBD-dominant. We assign it from the ratio of total THC to total CBD in a strain’s lab results: THC-dominant at 5 to 1 or more, CBD-dominant at 1 to 5 or less, balanced in between.
- Phenotype
- A plant’s observable traits, such as its shape, color, aroma or chemistry. The phenotype comes from the plant’s genotype together with its environment, so the same genetics can turn out differently in different conditions.
- Genotype
- A plant’s genetic make-up at the places in its DNA being compared. Two plants with the same genotype can still differ in phenotype if they grow in different conditions.
- Landrace
- A traditional crop population kept and adapted in one region over a long time, rather than bred to a fixed modern standard. Definitions vary, and a leading review of the term says no single all-embracing definition can be given.
- Heirloom
- An old, open-pollinated variety passed down from generation to generation. There is no fixed age cut-off, and in cannabis the word is used loosely for older lines kept going from seed.
- Hybrid
- In plant breeding, the offspring of two parents with different genotypes. On cannabis packaging, “hybrid” is also a label for plants said to be part indica and part sativa, which tells you little about their genetics.
- Cross
- The offspring of two parent plants bred together, usually written with “×”, as in “Parent A × Parent B”. A strain’s listed cross is what its breeder or the records claim, which is why we grade lineage.
- F1Also: F1 hybrid
- The first generation of offspring from a cross between two parents. “F” stands for filial.
- S1
- Seeds from a plant pollinated with its own pollen (“selfed”). In breeding notation, “S” marks generations of self-pollination, so S1 is the first.
- Backcross (BX)Also: BX, BX1, BC1, backcrossed
- Crossing offspring back to one of its parents, the “recurrent parent”, usually to keep that parent’s character while bringing in a trait from the other. BX1 (or BC1) marks the first backcross generation.
- IBLAlso: inbred line
- Inbred line: a line bred within itself for many generations until its plants are genetically uniform for the traits that matter, so they “breed true” from seed. In cannabis, “IBL” is a breeder’s description of a line.
- CutAlso: cutting, clone
- One particular plant kept going by taking cuttings, which are genetic copies of it, usually known by the strain name plus a nickname or number. Two cuts sold under the same strain name can be different plants.
- Clone-only
- A strain said to exist only as cuttings from one original plant, with no seed version from the original source. Seeds sold under the same name grow into new plants with their own genetics.
- PhenoAlso: pheno hunting, phenotype hunting
- Short for phenotype. Breeders use it for one individual plant chosen from a batch of seedlings, often numbered, as in “#4”; “pheno hunting” means picking out individual plants from seed for their traits.
- Feminized seedAlso: feminised seed, feminized seeds
- Seed bred so that nearly all the plants are female. It comes from a female plant made to produce pollen, so both parents are genetically female.
- AutoflowerAlso: autoflowering, auto
- A plant that flowers with age rather than in response to day length; botanists call this photoperiod-insensitive or day-neutral. The trait is linked to high-latitude cannabis that some classify as ruderalis.
- Indica
- A species name Lamarck gave to cannabis in 1785 (Cannabis indica). On packaging today, “indica” is a marketing label: a genome-wide study found indica- and sativa-labeled samples genetically indistinct, with the labels linked to a small number of terpenes.
- Sativa
- The species name Linnaeus gave cannabis in 1753 (Cannabis sativa), which has priority in botanical naming. As a retail label, “sativa” means something different from the species name and doesn’t mark a distinct genetic group.
- Ruderalis
- A name for wild or weedy cannabis from high latitudes, described in 1924 and usually treated as a variety rather than a species. Recent genomic studies don’t support it as a separate group.
- Name clash
- When different plants are sold under the same strain name, or one plant under several names. In one study of US lab data, 96% of product averages named Purple Punch fell in one terpene group, but only 62.5% of those named Tangie did.
- Alias
- Another name for the same strain, such as a shortened or older name. We list an alias only when a source supports it, and treat look-alike names, such as a numbered selection, as separate strains.
Chemistry25 terms
- CannabinoidAlso: cannabinoids
- A family of compounds made by the cannabis plant, including THC, CBD and CBG. In the plant, most of them occur as acids.
- Phytocannabinoid
- A cannabinoid made by a plant (“phyto” means plant). A 2021 review counted 125 cannabinoids isolated or identified in cannabis, among more than 500 compounds found in the plant.
- Acid formAlso: cannabinoid acid, acidic cannabinoid
- The form in which the plant makes most cannabinoids, carrying an extra carboxyl group (COOH). Their names end in A: THCA, CBDA, CBGA.
- DecarboxylationAlso: decarb, decarboxylated
- The loss of a carboxyl group as carbon dioxide (CO₂). Cannabinoid acids are unstable when exposed to heat or light and turn into their neutral forms this way: THCA becomes Δ9-THC, and CBDA becomes CBD.
- CBGAAlso: cannabigerolic acid
- Cannabigerolic acid (C₂₂H₃₂O₄), the shared starting molecule from which the plant’s enzymes make THCA, CBDA and CBCA.
- THCAAlso: THC-A, THCa, tetrahydrocannabinolic acid
- Tetrahydrocannabinolic acid (C₂₂H₃₀O₄), the acid form of THC and the main cannabinoid in most cannabis flower. Labs that use liquid chromatography report it separately from Δ9-THC.
- Δ9-THCAlso: delta-9 THC, delta 9 THC, d9-THC, THC
- Δ9-tetrahydrocannabinol (C₂₁H₃₀O₂), the neutral form of THC, made when THCA loses CO₂. On a flower lab report it is usually much smaller than THCA.
- Total THC
- Δ9-THC plus THCA counted by its THC weight: Δ9-THC + 0.877 × THCA. The USDA’s testing rule calls 0.877 a “molecular mass conversion ratio”; some states add other forms, and Ohio’s total also includes Δ8-THC.
- CBDAAlso: cannabidiolic acid
- Cannabidiolic acid (C₂₂H₃₀O₄), the acid form of CBD, made from CBGA by its own enzyme. Total CBD is CBD + 0.877 × CBDA.
- CBDAlso: cannabidiol
- Cannabidiol (C₂₁H₃₀O₂), the neutral form of CBDA. It has the same formula as Δ9-THC but a different structure.
- CBGAlso: cannabigerol
- Cannabigerol (C₂₁H₃₂O₂), the neutral form of CBGA. Total CBG is CBG + 0.878 × CBGA, a slightly different factor because both molecules are a little heavier.
- CBCAlso: cannabichromene
- Cannabichromene (C₂₁H₃₀O₂), the neutral form of CBCA, an acid the plant makes from CBGA.
- CBNAlso: cannabinol
- Cannabinol (C₂₁H₂₆O₂). It isn’t made by the plant’s enzymes: it forms when THC is oxidized, for example when heated.
- THCVAlso: tetrahydrocannabivarin, THCVA
- Tetrahydrocannabivarin (C₁₉H₂₆O₂), a cannabinoid with the same ring structure as THC but a shorter, three-carbon (propyl) side chain in place of THC’s five-carbon one. Its acid form is THCVA.
- TerpeneAlso: terpenes
- A compound built from five-carbon isoprene units, made by many plants as part of their aroma. Strictly, terpenes are hydrocarbons; on this site, as on most lab reports, “terpene” also covers oxygen-containing terpenoids such as linalool.
- Terpenoid
- A compound derived from isoprene units that contains oxygen, such as linalool, an alcohol. Lab reports usually list terpenes and terpenoids together as “terpenes”.
- MonoterpeneAlso: monoterpenes
- A terpene with 10 carbons, built from two isoprene units, such as myrcene, limonene and pinene. In one early study, the monoterpene share of cannabis bud oil fell as the buds dried.
- SesquiterpeneAlso: sesquiterpenes
- A terpene with 15 carbons, built from three isoprene units, such as caryophyllene and humulene.
- Isoprene
- A five-carbon building block. Terpenes are classed by how many isoprene units their carbon skeleton is formally built from: 10 carbons for a monoterpene, 15 for a sesquiterpene.
- Volatile sulfur compoundAlso: VSC, VSCs
- A sulfur-containing compound that evaporates easily. A 2021 study identified 3-methyl-2-butene-1-thiol as the main source of the skunk-like note in cannabis, which terpenes don’t explain.
- TrichomeAlso: trichomes, resin gland
- A tiny hair-like growth on a plant’s surface. The glandular trichomes on cannabis flowers, its resin glands, are where most of its cannabinoids and terpenes are made.
- Resin
- The sticky secretion of the glandular trichomes. Cannabis resin holds hundreds of different terpene and cannabinoid compounds.
- Entourage effect
- The idea that compounds in cannabis change one another’s effects. It is a hypothesis; evidence in people is limited. The term was first used in 1998, about compounds made in the body rather than in cannabis.
- Molar massAlso: molecular weight, molecular mass
- The mass of one mole of a substance, in grams per mole (g/mol). Δ9-THC’s molar mass (314.47 g/mol) divided by THCA’s (358.48 g/mol) gives the 0.877 in total THC; the difference, 44.01 g/mol, is one molecule of CO₂.
- PubChem CIDAlso: CID, PubChem
- The compound ID number in PubChem, the free chemistry database run by the US National Library of Medicine. Each terpene and cannabinoid page lists its CID so you can check the chemistry at source.
Lab reports22 terms
- COAAlso: certificate of analysis, lab report
- Certificate of analysis: a lab’s report of what it measured in a sample, such as cannabinoids, terpenes, moisture and contaminant tests. It names the lab, the sample and its batch, and the dates.
- BatchAlso: lot, batch ID, lot ID
- A quantity of product made or harvested together and tracked under one ID. A COA describes the batch its sample came from, not every batch sold under the same name.
- Sample ID
- The lab’s identifier for the sample it tested. It should match the ID on the package or in the state tracking record.
- PotencyAlso: potency test, cannabinoid profile
- On a lab report, the cannabinoid results, such as THCA, Δ9-THC and CBD, usually in % or mg/g. It measures how much of each compound is in the sample, nothing more.
- Dry weightAlso: dry weight basis, dry-weight
- Results calculated as if the sample’s water had been removed, so they read higher than as-received results for the same sample. States differ: Vermont requires dry weight for flower potency, while Ohio and Washington report results as received.
- As receivedAlso: as is, wet weight
- Results for the sample as it arrived at the lab, with its water included.
- Moisture contentAlso: moisture
- The share of a sample’s weight that is water. Labs use it to convert results between an as-received and a dry-weight basis.
- Water activityAlso: aw, aw
- A lab measure of the “free” water in a sample, on a scale from 0 to 1 (written aw). Washington’s testing rule uses water activity as its moisture test for flower.
- Contaminant testingAlso: safety panel, contaminant panel
- Tests for things such as pesticides, mycotoxins, microbes and foreign matter, judged against limits that each state sets. Washington, for example, requires flower to be tested for these as well as for potency and moisture.
- LODAlso: limit of detection, detection limit
- Limit of detection: the lowest amount of a compound a method can detect, though not necessarily measure as an exact value. Below it, a result is reported as ND.
- LOQAlso: limit of quantitation, limit of quantification, quantitation limit
- Limit of quantitation: the lowest amount a method can measure with suitable precision and accuracy. Results between the LOD and the LOQ are often printed as “<LOQ”.
- NDAlso: not detected, non-detect
- Not detected: the compound was tested for but was below the limit of detection. ND isn’t the same as zero, and it isn’t the same as “not tested”.
- HPLCAlso: liquid chromatography, LC
- High-performance liquid chromatography, a lab method that separates compounds in a liquid. Because it doesn’t heat the sample, it measures cannabinoid acids such as THCA separately from their neutral forms.
- GC-MSAlso: gas chromatography, GC
- Gas chromatography–mass spectrometry, a lab method that vaporizes a sample, separates its compounds and identifies them by their mass. Labs use it to measure terpenes; for cannabinoids, its heat turns acids into neutral forms unless the sample is treated first.
- Terpene panel
- The list of terpenes a lab tests for. Panels differ from lab to lab, so a terpene missing from a report may simply not have been tested; we count a terpene only where it was on the panel.
- Total terpenes
- The sum of the terpenes measured on a lab’s panel, in mg/g or %. It depends on the panel and on drying and storage, so we grade it no higher than C.
- mg/gAlso: milligrams per gram
- Milligrams per gram: how many milligrams of a compound are in each gram of sample. 10 mg/g is the same as 1%.
- % w/wAlso: percent by weight, weight percent
- Percent by weight: grams of a compound per 100 grams of sample. A THCA result of 24% means 24 g in every 100 g, or 240 mg/g.
- Lab inflationAlso: THC inflation
- THC results that read higher than the same product would test elsewhere. Studies have found systematic differences between US testing labs, and retail labels reading higher than independent retests.
- Lab shopping
- Choosing a testing lab for the results it tends to report rather than for its accuracy. Because labs differ systematically, we cap any one lab’s share of a strain’s figure at 30%.
- Retest
- A second test of the same batch, by the same lab or another one. When a retest differs from the first result, it shows how much a single test can vary.
- MetrcAlso: Metrc Retail ID, Retail ID, state tracking, seed-to-sale tracking
- A seed-to-sale tracking system that many US state regulators use to follow cannabis from plant to package. Its Retail ID QR codes, used in about 20 markets as of mid-2025, open a package’s record, including its test results.
How we grade data15 terms
- Evidence gradeAlso: grade, data grade, grade A, grade B, grade C, grade D
- Our A to D grade for how much data stands behind a figure. Grade A needs at least 30 results from at least 3 labs and 2 states or datasets, some from the last 5 years, with no lab above 30%; B is 10 to 29 results, or more that miss an A condition; C is 3 to 9. Grade D, fewer than 3, prints “Not yet measured” instead of a number.
- nAlso: sample size
- The number of lab results, profiles or strains behind a figure. We print it beside every lab figure on the site.
- Median
- The middle value when results are put in order: half are lower and half are higher. We use medians because a few unusual results move them less than an average.
- Middle halfAlso: interquartile range, IQR, p25–p75
- The range between the 25th and 75th percentiles of results, where the middle 50% fall. A quarter of results are below it and a quarter above.
- Percentile
- A value’s position in a ranked list: the 80th percentile is higher than 80% of the values. A strain’s THC percentile ranks its median against all strains with THC graded A to C.
- Top 1% trim
- For strains with 100 or more THC results, we drop the highest 1% before working out the figures, so a few extreme results can’t pull the range up.
- Per-lab cap
- No single lab and no single producer may make up more than 30% of the weight behind a strain’s figure, so one source can’t decide it.
- Lineage gradeAlso: L1, L2, L3, L4
- Our L1 to L4 grade for each claimed parent. L1 means the breeder states it; L2 adds a consistent genetic report; L3 means two independent secondary sources, with the breeder silent. L4 is disputed or unknown, and is drawn as a dashed line.
- Grow gradeAlso: G1, G2, G3
- Our G1 to G3 grade for grow facts, which are always breeder claims. G1 comes from the breeder’s own site or pack, and G2 from a reseller quoting the breeder; G3 has no primary source and is never shown.
- TierAlso: Tier A, Tier B, Tier C, data tier
- Whether a strain page is complete. Tier A pages have graded lab data and sourced history, and are indexed by search engines. Tier B pages are stubs still being built, and Tier C names are aliases that redirect to the main page.
- ReleaseAlso: data release
- A dated version of our data, such as 2026-10-20. Each release records its sources, method version and changes, so any figure can be traced back.
- Profile overlap
- How alike two terpene profiles are: for each terpene, take the smaller of the two shares, then add them up. Identical profiles overlap 100%; profiles with no terpene in common overlap 0%.
- Similarity score
- How we pick similar strains: mostly how alike their whole terpene profiles are, compared on a log-ratio scale, plus a smaller weight for how close their THC and CBD are. It describes chemistry, never effects.
- Log-ratioAlso: centered log-ratio, CLR
- A way to compare shares that add up to 100% by looking at each share relative to the others, on a logarithmic scale. It treats “twice as much myrcene as pinene” the same way whatever the total.
Name words9 terms
- OG
- A name word in many strain names, as in OG Kush and the strains named after it. What the letters first stood for is disputed, and the stories differ, so we don’t pick one.
- Kush
- A name word that, according to common accounts, refers to the Hindu Kush, the mountain range that runs through Pakistan into Afghanistan. Today it marks strains claimed to descend from Kush lines rather than any proven origin.
- Haze
- A name word for strains claimed to descend from an older line called Haze. Its history comes from breeders’ accounts, which differ.
- Diesel and ChemAlso: Diesel, Chem, Chemdog
- Name words for strains claimed to descend from the Chemdawg and Sour Diesel lines, which were named for a fuel-like or chemical aroma.
- Cookies
- A name word for strains claimed to descend from GSC, and for the many crosses named after it. We use the short name GSC for the original.
- Cake
- A name word in dessert-style strain names, such as Wedding Cake. Like other name words, it signals a claimed family or a naming style, not a measured trait.
- Gelato
- A name word for the strain Gelato and its family. A number after the name, as in “Gelato #33”, usually marks a separate plant selected from the same seeds, so we treat numbered versions as separate strains.
- Purple
- A name word for strains with purple color. The purple in cannabis comes from anthocyanin pigments, and how much a plant makes depends on both its genetics and its conditions.
- Exotic
- A marketing term for newer strains with unusual aromas. A 2023 study, by authors from a terpene company, defined “exotic” as varieties that are unusually sweet or savory, and traced those aromas to minor compounds that aren’t terpenes.