WordReference Random House Learner's Dictionary of American English © 2026
in•val•i•date /ɪnˈvælɪˌdeɪt/USA pronunciation
v. [~ + object], -dat•ed, -dat•ing.
WordReference Random House Unabridged Dictionary of American English © 2026- to discredit; show that (something) is incorrect:This new finding invalidates his previous argument.
- to deprive of legal force;
nullify:The judge invalidated the guilty verdict and set the defendant free.
in•val•i•date
(in val′i dāt′),USA pronunciation v.t., -dat•ed, -dat•ing.
in•val′i•da′tion, n.
in•val′i•da′tor, n.
- to render invalid;
discredit. - to deprive of legal force or efficacy;
nullify.
- invalid2 + -ate1 1640–50
in•val′i•da′tor, n.
- 1. weaken, impair; disprove, refute, rebut.
'invalidation' also found in these entries (note: many are not synonyms or translations):