Cannabis has its own vocabulary, and it can feel overwhelming when you are just getting started. This glossary defines the key terms you will encounter on TryCannabis.org and in the broader cannabis world. Every definition is written for a general audience — no science degree required.
Bioavailability
The percentage of a substance that actually enters your bloodstream and produces active effects. Bioavailability varies significantly by consumption method. Inhalation (smoking or vaping) has the highest bioavailability — roughly 30 to 50% of the cannabinoids reach your blood. Edibles have much lower bioavailability (around 4 to 20%) because the compounds must pass through your digestive system and liver before reaching circulation. Sublingual products (tinctures held under the tongue) fall somewhere in between.
Why it matters: Bioavailability explains why 10 mg of THC in an edible feels different from 10 mg inhaled. The amount that reaches your system varies, which affects both the intensity and duration of effects. Learn more on our Methods of Consumption page.
Biphasic Effect
A phenomenon where a substance produces opposite effects at low versus high doses. This is one of the most important concepts in cannabis therapeutics. At low doses, THC tends to reduce anxiety and promote relaxation. At higher doses, the same compound can increase anxiety, cause paranoia, and produce discomfort. The threshold varies from person to person.
Why it matters: The biphasic effect is the scientific basis for the "start low and go slow" approach to dosing. More is not always better with cannabis — sometimes less is significantly more effective. See Dosing Fundamentals.
Budtender
A trained staff member at a licensed cannabis dispensary who helps customers select products. Budtenders can answer questions about product types, potency, terpene profiles, and consumption methods. The quality of training and knowledge varies widely between dispensaries. A good budtender can be an excellent resource, but their recommendations should complement — not replace — advice from your healthcare provider.
Why it matters: If you are visiting a dispensary for the first time, your budtender is your first point of contact. Knowing what questions to ask can make a big difference. See What to Expect at a Dispensary.
Cannabinoid
A chemical compound that interacts with the endocannabinoid system. Cannabinoids come in three forms: endocannabinoids (produced naturally by your body, such as anandamide and 2-AG), phytocannabinoids (produced by the cannabis plant, such as THC and CBD), and synthetic cannabinoids (manufactured in a laboratory). The cannabis plant produces over 100 unique cannabinoids, though THC and CBD are the most studied and well-known.
Why it matters: Different cannabinoids produce different effects. Understanding which cannabinoids are in a product helps you predict how it might affect you. See Cannabinoids & Terpenes.
Cannabis Use Disorder (CUD)
A clinical diagnosis characterized by problematic cannabis use that causes significant impairment or distress. Diagnostic criteria include developing tolerance (needing more to achieve the same effect), experiencing withdrawal symptoms when stopping, being unable to cut back despite wanting to, spending excessive time obtaining or using cannabis, and continuing use despite negative consequences in relationships, work, or health. Research suggests approximately 9% of people who use cannabis will develop some degree of CUD, with the risk higher for those who start young or use daily.
Why it matters: While cannabis has a lower addiction risk than many substances, it is not zero. Honest self-assessment is important. See Cannabis Use Disorder.
CBD (Cannabidiol)
A non-psychoactive cannabinoid found in cannabis, meaning it does not produce the "high" associated with THC. CBD is the second most abundant cannabinoid in the cannabis plant and has been widely studied for seizure disorders, anxiety, and inflammation. The FDA has approved one CBD medication — Epidiolex — for certain severe pediatric seizure disorders. CBD is marketed widely for pain relief, anxiety, and sleep, though the evidence for pain relief specifically is limited at the doses found in most consumer products.
Why it matters: CBD is often marketed as a cure-all, but the evidence is more nuanced. It has proven benefits for specific conditions, but many claims remain unproven at typical consumer doses.
Certificate of Analysis (COA)
A lab report showing the detailed chemical composition of a cannabis product. A COA typically includes the cannabinoid profile (how much THC, CBD, and other cannabinoids are present), the terpene profile, and results from safety testing for contaminants such as pesticides, heavy metals, residual solvents, and mold. Reputable dispensaries make COAs available for every product they sell, either on the packaging, via a QR code, or upon request.
Why it matters: A COA is your proof that a cannabis product contains what it claims to contain and is free of harmful contaminants. Always check the COA, especially for products purchased online. See Reading Lab Results.
CYP450 (Cytochrome P450)
A family of enzymes in the liver responsible for metabolizing (breaking down) the majority of pharmaceutical medications. Both THC and CBD can inhibit certain CYP450 enzymes, which means they can slow down the metabolism of other drugs in your system. When a medication is broken down more slowly, its blood levels can rise higher than expected, potentially increasing both its effects and its side effects.
Why it matters: CYP450 interactions are the primary reason cannabis can affect how your other medications work. This is critically important for anyone taking blood thinners, anti-seizure medications, certain heart drugs, or immunosuppressants. Always discuss cannabis use with your prescribing physician. See Drug Interactions.
Edible
Any cannabis-infused food or beverage product, including gummies, chocolates, baked goods, beverages, mints, and capsules. Edibles are processed through the digestive system and liver before reaching the bloodstream, which means they take longer to take effect (typically 30 minutes to 2 hours) and produce effects that last longer (4 to 8 hours or more). Because of first-pass metabolism in the liver, THC is converted to 11-hydroxy-THC, which is more potent and longer-lasting than inhaled THC.
Why it matters: The delayed onset of edibles is the most common cause of accidental overconsumption by new users. The golden rule: start with a very low dose (2.5 to 5 mg THC), wait at least 2 hours before taking more, and never assume "it is not working" as a reason to take a second dose too soon.
Endocannabinoid System (ECS)
A biological signaling system present in every human body, consisting of three components: endocannabinoids (molecules your body naturally produces, primarily anandamide and 2-AG), cannabinoid receptors (CB1 receptors concentrated in the brain and nervous system, and CB2 receptors found primarily in immune tissues), and enzymes (FAAH and MAGL, which break down endocannabinoids after use). The ECS regulates homeostasis — the stability of your internal environment — and is involved in pain, mood, sleep, appetite, immune function, and many other processes.
Why it matters: The ECS is the reason cannabis works in the human body. Plant cannabinoids interact with the same system your own endocannabinoids use. See The Endocannabinoid System.
Entourage Effect
The theory that the various compounds in cannabis — cannabinoids, terpenes, flavonoids, and other molecules — work synergistically, producing therapeutic effects that are greater than any single compound used in isolation. For example, CBD may modulate some of the anxiety-producing effects of THC, while certain terpenes may enhance pain relief. The concept was first described by Dr. Raphael Mechoulam and is widely accepted among cannabis clinicians, though rigorous clinical proof is still developing.
Why it matters: The entourage effect is the reason many clinicians and patients prefer full-spectrum cannabis products over isolated compounds. It suggests that the whole plant may be more therapeutic than any single extracted ingredient.
First-Pass Metabolism
The process by which the liver metabolizes a substance before it reaches systemic circulation (the rest of the body). When you eat a cannabis edible, THC passes through your stomach and into the liver, where it is converted into 11-hydroxy-THC — a metabolite that is more potent and longer-lasting than regular THC. This is why edibles often produce stronger and different effects than inhaled cannabis, even at comparable doses.
Why it matters: First-pass metabolism is the key scientific reason why edibles hit differently. It explains both the delayed onset and the increased intensity compared to smoking or vaping.
Full-Spectrum
A cannabis product that contains the complete range of cannabinoids, terpenes, flavonoids, and other compounds found in the original plant material. This is in contrast to isolate products (which contain only a single compound, such as pure CBD) and broad-spectrum products (which contain multiple compounds but have had THC removed). Full-spectrum products are designed to preserve the entourage effect.
Why it matters: When shopping for cannabis products, understanding the spectrum helps you choose products aligned with your goals. Full-spectrum products may offer more comprehensive therapeutic effects but will contain THC.
Homeostasis
The body's ongoing process of maintaining stable internal conditions despite changes in the external environment. When you get too hot, you sweat. When blood sugar drops, you feel hungry. These are examples of homeostatic processes. The endocannabinoid system is one of the body's primary homeostatic regulators, acting like a master dimmer switch that adjusts the activity of other biological systems up or down as needed to maintain balance.
Why it matters: Homeostasis is the "why" behind the endocannabinoid system. Understanding that the ECS exists to maintain balance helps explain why cannabis can affect so many different bodily functions — it is interacting with a system that touches nearly everything.
Indica / Sativa
A traditional classification system for cannabis varieties (strains). Indica strains are popularly described as relaxing, sedating, and body-focused, while sativa strains are described as energizing, uplifting, and cerebral. However, modern research has shown that this classification is largely outdated and scientifically unreliable. The actual effects of a cannabis product depend far more on its specific cannabinoid and terpene profile than on whether it was labeled indica or sativa. Many products sold as "indica" and "sativa" have nearly identical chemical compositions.
Why it matters: While you will still see these terms in every dispensary, they should not be the primary basis for your product selection. Ask about the cannabinoid content (THC/CBD percentages) and terpene profile instead. See Cannabinoids & Terpenes.
Microdosing
The practice of consuming very small amounts of cannabis — typically 1 to 5 mg of THC — to achieve therapeutic benefits without significant psychoactive impairment. Microdosing is based on the principle that, for many conditions, the minimum effective dose produces the best results with the fewest side effects. Many patients who microdose report being able to manage symptoms like anxiety, pain, or inflammation while remaining fully functional throughout the day.
Why it matters: Microdosing is particularly relevant for beginners and for anyone who wants therapeutic benefits without feeling "high." It aligns directly with the biphasic effect — lower doses often work better than higher ones, especially for anxiety. See Dosing Fundamentals.
Terpene
An aromatic compound found in cannabis and many other plants, including lavender, citrus fruits, pine trees, and black pepper. Terpenes are responsible for the distinctive smell and flavor of different cannabis varieties. More importantly for therapeutic purposes, emerging research suggests that terpenes may have their own medicinal properties and may interact with cannabinoid receptors to influence the overall effects of cannabis. Common cannabis terpenes include myrcene (earthy, sedating), limonene (citrus, uplifting), linalool (floral, calming), and pinene (pine, alert).
Why it matters: Terpenes may be as important as cannabinoids in determining how a cannabis product will affect you. Learning to read terpene profiles on product labels can help you select products more effectively. See Cannabinoids & Terpenes.
THC (Tetrahydrocannabinol)
The primary psychoactive cannabinoid in cannabis and the compound responsible for the "high." THC binds directly to CB1 receptors in the brain, mimicking the action of the body's own endocannabinoid anandamide but lasting much longer. It is the most studied cannabinoid for pain relief, nausea reduction, appetite stimulation, and muscle spasm reduction. THC content in modern cannabis products ranges from around 10% to over 30%, with concentrates reaching 80% or higher.
Why it matters: THC is the compound most associated with both the therapeutic benefits and the risks of cannabis. Understanding THC content and how it affects you personally is fundamental to responsible use.
Tincture
A liquid cannabis extract, typically dissolved in alcohol or oil (such as MCT coconut oil), that is administered using a dropper. Tinctures are most commonly taken sublingually (under the tongue), where the cannabinoids are absorbed directly into the bloodstream through the mucous membranes. This bypasses first-pass metabolism, providing faster onset than edibles (typically 15 to 45 minutes) with more precise dosing control. Tinctures can also be swallowed or added to food, though they will then be processed like an edible.
Why it matters: Tinctures are often recommended for beginners because they allow very precise dose control (down to fractions of a milligram with a calibrated dropper) and provide a middle ground between the immediacy of inhalation and the duration of edibles.
Titration
The process of gradually adjusting a dose upward (or downward) until the desired therapeutic effect is achieved with minimal side effects. In cannabis therapeutics, titration is the cornerstone of responsible dosing — often expressed as "start low and go slow." You begin with the lowest possible dose, wait to assess the effects, and make small, incremental adjustments over days or weeks until you find your personal optimal dose. This approach accounts for the wide variation in individual responses to cannabis.
Why it matters: Titration is the single most important dosing concept. Everyone's optimal dose is different, and finding yours requires patience and careful self-observation. See Dosing Fundamentals.
Tolerance
The body's adaptation to regular cannabis use, resulting in a diminished response to the same dose over time. With regular use, your brain reduces the number of available CB1 receptors (a process called downregulation), meaning you need more cannabis to achieve the same effects. Tolerance develops at different rates for different effects — tolerance to the "high" develops relatively quickly, while tolerance to pain-relieving effects may develop more slowly. The good news is that cannabis tolerance is largely reversible: a "tolerance break" (abstaining for days to weeks) allows receptors to return to baseline.
Why it matters: If you find yourself needing increasing amounts of cannabis to achieve the same results, tolerance is likely the explanation. Periodic tolerance breaks and dose adjustments are normal parts of long-term cannabis use.
Topical
A cannabis-infused product designed to be applied directly to the skin, such as creams, lotions, balms, salves, and patches. Standard topicals work locally — they interact with cannabinoid receptors in the skin and underlying tissue without entering the bloodstream in significant amounts. This means they generally do not produce psychoactive effects, making them an option for people who want localized relief (such as for joint pain or skin inflammation) without feeling high. Transdermal patches are a special category that are designed to deliver cannabinoids into the bloodstream and may produce systemic effects.
Why it matters: Topicals are an approachable starting point for people who are nervous about psychoactive effects. They offer localized relief with minimal systemic exposure. See Methods of Consumption.
This glossary is updated as new terms become relevant to the cannabis conversation. If there is a term you have encountered and cannot find here, let us know and we will add it.