Synonyms of affirm in English:

affirm


See definition of affirm

verb

1‘he affirmed that they would lend military assistance’

SYNONYMS
declare, state, assert, aver, proclaim, pronounce, attest, swear, avow, vow, guarantee, promise, certify, pledge, give one's word, give an undertaking
rare asseverate
ANTONYMS

deny

2‘the charter affirmed the right of national minorities to use their own language’

SYNONYMS
uphold, support, defend, maintain, confirm, ratify, endorse, approve, approve of, agree to, consent to, assent to, sanction