Grass

From Old English græs. Cannabis slang is first cited in 1943 (Green's Dictionary of Slang), almost certainly from the plant's green, clipping-like dried appearance. Peaked during the 1960s–1970s U.S. hippie counterculture and faded by the 1990s as "weed" rose. ⚠️ Minor disputed theories link it to a corruption of "hashish" or the Atharvaveda's "sacred grass"; both are unsupported by the OED. Now dated; associated with older speakers and period fiction. Chiefly North American and British usage.