pokeweed (n.)

"pokeweed; a strong-growing branching weed of eastern North America used in medicine and dyeing," colonial American English, from native words, possibly a confusion of similar-sounding Native American plant names; from 1630s in English as "tobacco plant," short for uppowoc (1580s), from Algonquian (Virginia) *uppowoc. Later (1708) the word is used in the sense "pokeweed," as a shortened form of puccoon, from Algonquian (Virginia) *puccoon, name of a plant used for dyeing. Native roots for "smoke" and "stain" have been proposed as the origin or origins.

"plant not valued for use or beauty," Old English weod, uueod "grass, herb, weed," from Proto-Germanic *weud- (source also of Old Saxon wiod, East Frisian wiud), of unknown origin. Also applied to trees that grow abundantly. Meaning "tobacco" is from c. 1600; that of "marijuana" is from 1920s. The chemical weed-killer is attested by 1885.