Meaning

noun any plant that crowds out cultivated plants

noun a black band worn by a man (on the arm or hat) as a sign of mourning

noun street names for marijuana

originFrom Scots weid, weed. The longer form weidinonfa, wytenonfa (Old Scots wedonynpha) is attested since the 1500s. Jamieson's Etymological Dictionary of the Scottish Language analyses the longer form as a compound meaning "onfa(ll) of a weed", whereas the Scottish National Dictionary/DSL considers the short form a derivative of the longer form, and derives its first element from Old English wēdan…

Etymology from Wiktionary, CC BY-SA 3.0