1) Thc 
Tetrahydrocannabinol (THC), or more precisely its main isomer (−)-``trans``-Δ9-tetrahydrocannabinol ({hsp}(6aR,10aR)-delta-9-tetrahydrocannabinol), is the principal psychoactive constituent (or cannabinoid) of the cannabis plant. First isolated in 1964 by Israeli scientists Raphael Mechoulam and Yechiel Gaoni at the Weizmann Institute of Sc...
active constituent of marijuana and hashish that was first isolated from the Indian hemp plant (Cannabis sativa) and synthesized in 1965. For the ... [1 related articles]
<chemical> The delta(1)-3,4-trans-isomer (also referred to as the delta(9)-isomer) is the major pharmacologically active constituent of cannabis sativa l. (marihuana, hashish). Dronabinol, a synthetic form of tetrahydrocannabinol, is used to treat the wasting condition associated with aids and also cancer patients undergoing chemotherapy. ......
(THC) (tet″rә-hi″dro-kә-nab´ĭ-nol) the active principle of cannabis (see marijuana and hashish); it occurs in two isomeric forms, both having euphoric effects on the brain.
A cannabinoid and one of the more psychoactive components of cannabis.
[n] - psychoactive substance present in marijuana
THC noun psychoactive substance present in marijuana