ūsurpātor

I. one who uses or takes possession unlawfully, a usurper of a thing (late Lat.): indebitae potestatis, Amm. 26, 7, 12: tanti nominis, Symm. Or. ap. Val. 1, 22.—

II. In gen., one who accomplishes: ardui operis, Jul. Sev. Syn. praef. 1.