mid-15c., originally in Latin grammar (of verbs passive in form but active in sense), from Latin deponentem "putting down or aside," present participle of deponere "lay aside, put down, deposit," also used of births and bets, from de "away" (see de-) + ponere "to put, place" (see position (n.)). As a noun, "a deponent verb," 1520s; as "one who makes a deposition," especially under oath, from 1540s.