Forms

Unprocessed

Dried Cannabis flowers in natural herbal form

The terms cannabis or marijuana generally refer to the dried flowers and subtending leaves and stems of the female cannabis plant.^{[citation needed]} This is the most widely consumed form, containing 3% to 22% THC.^[29][30] In contrast, cannabis varieties used to produce industrial hemp contain less than 1% THC and are thus not valued for recreational use.^[31]

Processed

Kief

Main article: Kief

Kief is a powder, rich in trichomes, which can be sifted from the leaves and flowers of cannabis plants and either consumed in powder form or compressed to produce cakes of hashish.^[32]

Hashish

Main article: Hashish

Hashish

Hashish (also spelled hasheesh, hashisha, or simply hash) is a concentrated resin produced from the flowers of the female cannabis plant. Hash can often be more potent than marijuana and can be smoked or chewed.^[33] It varies in color from black to golden brown depending upon purity.

Hash oil

BHO

Main article: Hash oil

Hash oil, or "butane honey oil" (BHO), is a mix of essential oils and resins extracted from mature cannabis foliage through the use of various solvents. It has a high proportion of cannabinoids (ranging from 40 to 90%).^[34] and is used in a variety of cannabis foods.

Residue (resin)

Because of THC's adhesive properties, a sticky residue, most commonly known as "resin", builds up inside utensils used to smoke cannabis. It has tar-like properties but still contains THC as well as other cannabinoids. This buildup retains some of the psychoactive properties of cannabis but is more difficult to smoke without discomfort caused to the throat and lungs. This tar may also contain CBN, which is a breakdown product of THC. Cannabis users typically only smoke residue when cannabis is unavailable. Glass pipes may be water-steamed at a low temperature prior to scraping in order to make the residue easier to remove.^[35]

Routes of administration

Main article: Cannabis consumption

A joint

A forced-air vaporizer. The detachable balloon (top) fills with vapors that are then inhaled.

A conduction vaporizer, with flexible extension tube ("whip"). A small serving of cannabis is heated on a metal platform (center).

Cannabis is consumed in many different ways, most of which involve inhaling vaporized cannabinoids ("smoke") from small pipes, bongs (portable version of hookah with water chamber), paper-wrapped joints or tobacco-leaf-wrapped blunts.
A vaporizer heats herbal cannabis to 365–410 °F (185–210 °C),^{[citation needed]} causing the active ingredients to evaporate into a vapor without burning the plant material (the boiling point of THC is 390.4 °F (199.1 °C) at 760 mmHg pressure).^{[36][not in citation given]} A lower proportion of toxic chemicals is released than by smoking, depending on the design of the vaporizer and the temperature setting. This method of consuming cannabis produces markedly different effects than smoking due to the flash points of different cannabinoids; for example, CBN (usually considered undesirable) has a flash point of 212.7 °C (414.9 °F)^[37] and would normally be present in smoke but not in vapor.
Fresh, non-dried cannabis may be consumed orally. However, the cannabis or its extract must be sufficiently heated or dehydrated to cause decarboxylation of its most abundant cannabinoid, tetrahydrocannabinolic acid (THCA), into psychoactive THC.^[38]
Cannabinoids can be extracted from cannabis plant matter using high-proof spirits (often grain alcohol) to create a tincture, often referred to as Green Dragon.
Cannabis can also be consumed as a tea. THC is lipophilic and only slightly water-soluble (with a solubility of 2.8 mg per liter),^[39] so tea is made by first adding a saturated fat to hot water (i.e. cream or any milk except skim) with a small amount of cannabis.

Websters Dictionary - Marijuana
 
WEBSTER'S ENCYCLOPEDIC DICTIONARY OF THE ENGLISH LANGUAGE Copyright 1957 - H.S. STUTTMAN Co.
(from page 2681) marijuana or marihuana (ma re hwa na) n. A weed or herb, growing in many parts of North America; the dried leaves of the plant, which have narcotic qualities when smoked in cigarettes; sometimes called the assassin of youth.
Marijuana, or Hashish, a subtle, crazing drug which is being surreptitiously sold in U.S. in the form of cigarettes. Narcotic officials named it 'The Assassin of Youth,' and state that it is as dangerous as a coiled rattlesnake. Its effects when smoked vary with different Individuals. It may make of its victim a philosopher, a joyous reveler, a mad insensate, or a fiendish murderer. Its purveyors whisper into the ears of Am. youth the wonders of a new cigarette with a real thrill, and without harmful effects. Students are lured to its use by promises of resultant keenness of mind, the easy solving of problems, an aid in exams. An addict was hanged in Baltimore in 1937 for a criminal assault on a ten-year-old girl. In Fla. a crazed youth killed his father, mother, two brothers, and a sister. In more than 30 cases of murder or degenerate sex crimes in 1937, marijuana proved to be a contributing cause. See Hashish.
(page 1976) HEMP (hemp) n. 1 A tough-fiberded plant from which rope and certain coarse fabrics are made. 2. Hashish, a narcotic and intoxicating drug obtained from the Indian hemp. 3. Slang. The rope used for hanging people. Hemp'en adj.
Hemp, commercial name for the textile fibers yielded by several unrelated plants, but strictly used only to describe those produced by Cannabis sativa, native to s. Russ., Per., and parts of China. This plant is characterized by a straight undivided stalk, usually from five to eight ft. high, but sometimes attaining a height of 18 ft. The best hemp comes from Italy; it is also cultivated in Russ., the Philippines and elsewhere. It is mostly used in the mfr. of rope and strong twine, and is woven into sail-cloth and fire-hose. For making canvas and sacking it has been largely replaced by jute, which is cheaper. The Arabs give the name hashish to a preparation of the leaves. Hemp also has useful medicinal properties.