[W/K] :: tetrahydrocannabinol

  marijuana \marijuana\ n.
     1. A strong-smelling Asian plant ({Cannabis sativa), also
        called hemp, from which a number of euphorogenic and
        halucinogenic drugs are prepared. The euphoric effect is
        predominently due to tetrahydrocannabinol ({THC). [Also
        spelled marihuana.]
  
     Syn: cannabis, ganja, pot, grass, marihuana, Cannabis
          sativa.
          [WordNet 1.5]
  
     2. The dried leaves or the female flowers of the hemp plant,
        which is smoked or chewed to obtain a euphoric effect. The
        flowers usually have a higher concentration of the active
        ingredient, tetrahydrocannabinol.
  
     Syn: cannabis, ganja, pot, grass, marihuana, dope, weed,
          gage, sess, sens, smoke, skunk, Mary Jane.
          [WordNet 1.5]

  tetrahydrocannabinol \tet`ra*hy`dro*can*nab"i*nol\
     (t[e^]t`r[.a]*h[imac]`dr[-o]*k[a^]n*n[a^]b"[i^]n[add]l), n.
     (Chem. & Med.)
     A chemical substance ({C21H20O2) which is produced by the
     hemp plant (Cannabis sativa), and is the physiologically
     active agent of dried preparations of that plant, called
     variously marijuana, hashish, ganja, hemp, etc.; also called
     THC. It causes the euphoric effect for which the
     preparations are smoked or chewed. It is used in medicine in
     a purified form as an antiemetic (an antinausea agent),
     especially in conjunction with chemotherapy of cancer. It
     occurs primarily as the [Delta]1-3,4-trans isomer, also
     called [Delta]9-THC, with small amounts of the
     [Delta]6-3,4-trans isomer detectable at about 1%. It is a
     controlled substance, classified as a hallucinogen, and its
     possession or distribution is illegal in almost all states of
     the United States. --MI11
     [PJC]

  Cannabis \Can"na*bis\, prop. n. [L., hemp. See Canvas.]
     1. (Bot.) A genus of a single species belonging to the order
        Uricace[ae]; hemp.
        [1913 Webster]
  
     2. The Indian hemp plant plant Cannabis sativa syn.
        Cannabis Indica. See Cannabis Indica, below.
        [PJC]
  
     Cannabis Indica, the Indian hemp, now considered a variety
        of the common hemp ({Cannabis sativa), originating in
        Asia but now grown widely around the world. It can be
        formed into a tough fiber that is used to make rope and
        tough fabric. The dried leaves and female flowers are
        smoked or chewed by people to produce a euphoric or
        hallucinogenic effect, caused mainly by the substance
        tetrahydrocannabinol (THC) contained in it. The
        THC-containing products of Cannabis are classified as a
        controlled substance, and posession and sale are illegal
        in most states of the United States. Once classified as a
        narcotic, the plant is now more commonly referred to in
        the category of euphoric or hallucinogenic agents.
        [1913 Webster +PJC]

  tetrahydrocannabinol
       n : psychoactive substance present in marijuana [syn: THC]