marijuana-
1918, alt. by influence of Sp. proper name Maria Juana "Mary Jane" from mariguan (1894), from Mex.Sp. marihuana, of uncertain origin.

"Marijuana ... makes you sensitive. Courtesy has a great deal to do with being sensitive. Unfortunately marijuana makes you the kind of sensitive where you insist on everyone listening to the drum solo in Iron Butterfly's 'In-a-Gadda-Da-Vida' fifty or sixty times." [P.J. O'Rourke, "Modern Manners," 1983]
pot (2)
"marijuana," 1938, probably a shortened form of Mexican Sp. potiguaya "marijuana leaves."
toke (n.)
1968, "inhalation of a marijuana cigarette or pipe smoke," U.S. slang, from earlier verb meaning "to smoke a marijuana cigarette" (1952), perhaps from Sp. tocar in sense of "touch, tap, hit" or "get a shave or part." In 19c. the same word in British slang meant "small piece of poor-quality bread," but this probably is not related.
bong
"water pipe for marijuana," 1960s, U.S. slang, said to have been introduced by Vietnam veterans, from Thai baung, lit. "cylindrical wooden tube."
muggle
"marijuana, a joint," 1926, originally mainly from New Orleans, of unknown origin.
roach (1)
1837, shortened form of cockroach (q.v.), in contemporary writing said to be from a polite desire to avoid the sexual connotation in the first syllable; meaning "butt of a marijuana cigarette" is first recorded 1938, perhaps from resemblance to the insect, but perhaps a different word entirely.

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