annul v. + Add to list US //ˈænəɫ// UK //ɐnˈʌl// an·nul SynonymsAntonymsEtymology Synonyms avoidcountermandinvalidateliftnullifyquashrepealreverserevokevoid Antonyms validateOriginLATannullō→OFRanuller→MEannullen→ENannul From Middle English annullen, from Old French anuller, from Latin annullō (“annihilate, annul”), from ad (“to”) + nūllus (“none, not any”).