to expel or remove from a place or position occupied: The bouncer ousted the drunk; to oust the Prime Minister in the next election.
2.
Law.to eject or evict; dispossess.
Origin: 1375–1425;late Middle English < Anglo-Frenchouster to remove, Old Frenchoster < Latinobstāre to stand in the way, oppose (ob-ob- + stāre to stand)
early 15c., from Anglo-Fr. oster (late 13c.), O.Fr. oster "put out, keep off, remove, avert" (Fr. ôter), from L. obstare "stand opposite to, block, hinder," from ob "against" + stare "to stand," from PIE base *sta- "to stand" (see stet).