Main Entry: an·nul

Pronunciation: \ə-ˈnəl\

Function: transitive verb

Inflected Form(s): an·nulled; an·nul·ling

Etymology: Middle English annullen, from Anglo-French annuller, from Late Latin annullare, from Latin ad- + nullus not any — more at null

Date: 15th century

1 : to reduce to nothing : obliterate
2 : to make ineffective or inoperative : neutralize <annul the drug's effect>
3 : to declare or make legally invalid or void <wants the marriage annulled>

synonyms see nullify