late 14c., "thing of little use or value, waste, refuse, dross," perhaps from a Scandinavian source (compare Old Norse tros "rubbish, fallen leaves and twigs," Norwegian dialectal trask "lumber, trash, baggage," Swedish trasa "rags, tatters"), of unknown origin. Applied to ill-bred persons or groups from 1604 ("Othello"), and especially of poor whites in the U.S. South by 1831. Applied to domestic refuse or garbage from 1906 (American English). Trash-can is attested from 1914. To trash-talk someone or something is by 1989.
"to discard as worthless," 1859, from trash (n.); in the sense of "destroy, vandalize" it is attested from 1970; extended to "criticize severely" in 1975. Related: Trashed; trashing.