What is weed? In a conversation about cannabis, “weed” is an informal name for cannabis material or products. In South Africa, you will also encounter “dagga”. These everyday words do not tell you the exact plant variety, chemical composition, legal status or medical value of the item being discussed.
This guide explains the terms you are likely to see in an article, product description or conversation. It distinguishes the plant's name from compounds such as THC and CBD, and separates a definition from a claim about effects or permissions. If your question is about South African law or identifying a plant by appearance, the relevant specialist guides are linked below.
Weed, dagga, marijuana and cannabis
“Cannabis” is the most useful general term when discussing the plant and its derived materials. “Weed” and “dagga” are informal names whose exact meaning depends on context. “Marijuana” is also widely used, particularly for material associated with THC.
The US National Center for Complementary and Integrative Health explains the distinction between the broad term cannabis and the way marijuana is used for THC-containing material. Its discussion of US legal categories should not be treated as South African law.
There is another ordinary meaning of “weed”: a plant growing where it is unwanted. A gardening article using that word may have nothing to do with cannabis. Read the surrounding sentence before assuming which meaning is intended.
| Term | Useful reading of the term | What it does not tell you |
|---|---|---|
| Cannabis | The plant or materials derived from it, depending on context | The composition of a particular sample |
| Weed or dagga | Informal cannabis terminology | A measured strength or a legal entitlement |
| Marijuana | A common term often associated with THC-containing cannabis | A complete chemical description |
| THC | A named cannabinoid | The concentration in an untested product |
| CBD | A different named cannabinoid | That a product is risk-free or medically approved |
| Hemp | A term used for certain cannabis crops and products | A universal legal definition across countries |
What plant is being discussed?
Kew's Plants of the World Online recognises Cannabis sativa L. as an accepted name. Botanical references and commercial labels do not always organise the subject in the same way, which is one reason familiar words can be confusing.
The terms indica, sativa and hybrid often appear in commercial descriptions. Do not read them as precise chemical specifications. A label can tell you how a seller categorised something without establishing its exact ancestry or composition.
For that narrower question, see cannabis types by appearance. That guide explains why visible traits and category names have limits, rather than assigning predictable effects to a leaf shape.
THC and CBD are compounds, not plant names
THC and CBD are cannabinoids associated with cannabis. THC is principally responsible for the intoxicating effects commonly associated with marijuana. CBD is chemically distinct; the presence of CBD does not by itself establish the safety, quality or effectiveness of a finished product. The NCCIH fact sheet discusses these distinctions and evidence limitations.
A product described as “cannabis” is therefore not fully described. Which material is it? Which compounds have been measured? Does any analysis refer to this product and batch? Those questions are more precise than assuming everything called weed has the same composition.
The same care is needed with numbers on a label. A percentage without the named substance, measurement basis and a traceable sample record leaves important information unstated. A general glossary cannot authenticate an individual product.
Image colour does not establish cannabinoid content.
Historical use is not evidence for every modern claim
Cannabis has a history of different social and material uses; Kew's entry records uses including food, fibre and medicine. That history helps explain why the plant appears in several kinds of discussion. It does not validate every modern claim attached to its name.
Keep a claim's purpose visible. A statement about traditional use is a historical statement. A claim that a particular product treats a condition requires evidence for that product and use. A claim about a regulated medicine concerns its specific formulation and authorised use, not every item derived from the same plant.
This distinction is especially useful when an article moves from cultural history into an equipment advertisement. The historical paragraph does not establish the performance of the equipment, and the equipment listing does not establish a medical benefit.
Does the name tell you what is legal in South Africa?
No. A definition of weed or dagga is not a determination of which activities are permitted. Legal questions depend on the activity and the applicable rules, not merely the informal word used to describe the plant or product.
Use the separate South African cannabis law guide for that topic and check the official sources linked there. Do not borrow a foreign hemp threshold or a commercial label as proof of South African permission.
If you are reading a confusing claim, identify the question first: meaning, plant identity, chemistry, health evidence or law. Then look for the evidence that answers that particular question. “Weed” is a useful everyday word, but it is only the beginning of a precise description.