As a Noun:
1. A type of drug which is smoked in cigarettes and which is illegal in most countries. English = marijuana. Informal English = pot, grass, weed, dope.
2. A cigarette made of marijuana. Informal English = joint.
As a Verb or Adjective:
1. To put a marijuana cigarette in your mouth, suck the smoke into your lungs and blow it out again. English = smoke marijuana, smoke a marijuana cigarette. Informal English = smoke dope, smoke pot, smoke a joint.