- 1[intransitive, transitive] if something overturns, or if someone overturns it, it turns upside down or on its side The car skidded and overturned. overturn something He stood up quickly, overturning his chair.
- 2 [transitive] overturn something to officially decide that a legal decision etc. is not correct, and to make it no longer valid to overturn a decision/conviction/verdict His sentence was overturned by the appeals court.
NAmE//ˌoʊvərˈtərn//Verb Forms present simple I / you / we / they overturn
he / she / it overturns
past simple overturned
-ing form overturning