v.
Pronunciation: ( ˌ )in- ' va-l ə - ˌ d ā t
Function: transitive verb
Date: 1649
: to make invalid especially : to weaken or destroy the cogency of
synonyms see NULLIFY
– in · val · i · da · tion \ - ˌ va-l ə - ' d ā -sh ə n \ noun
– in · val · i · da · tor \ in- ' va-l ə - ˌ d ā -t ə r \ noun