- A very common street and recreational drug that comes from the marijuana plant. The plant that produces marijuana, as is well known, is the hemp plant cannabis sativa. The pharmacologically active ingredient in marijuana is tetra-hydro-cannabinol. Marijuana is used to heighten perception, affect mood and relax. It is estimated that about 30% of adults in the U.S. use marijuana. Many people think marijuana is harmless. It is not. Signs of marijuana use include red eyes, lethargy and uncoordinated body movements. The long-term effects may include decrease in motivation and harmful effects on the brain, heart, lung and reproductive system. People who smoke marijuana are more likely to develop cancer of the head and neck. The more often a person smokes marijuana and the longer they continue to smoke it, the greater is their chance of developing cancer in places such as the mouth, tongue, larynx or pharynx.
* * *mar·i·jua·na also mar·i·hua·na .mar-ə-'wän-əalso -'hwän- n1) HEMP (1)2) the dried leaves and flowering tops of the pistillate hemp plant that yield THC and are sometimes smoked in cigarettes for their intoxicating effect compare BHANG, CANNABIS, HASHISH
* * *n.
* * *mar·i·jua·na (mar″ĭ-hwahґnə) [Mexican Sp.] 1. Cannabis sativa. 2. a crude preparation of the leaves and flowering tops of C. sativa, usually employed in cigarettes and inhaled as smoke for its euphoric properties. See cannabis.
Medical dictionary. 2011.