certify

1 to declare (something) to be true or genuine experts certified the letter as indeed having been written by Abraham Lincoln Synonyms attest, authenticate, avouch, testify (to), vouch (for), witness Related Words guarantee, warrant; affirm, assert, aver, avow, profess, vow

2 to give official or legal power to certified her as a teacher Synonyms accredit, authorize, charter [British], commission, empower, enable, invest, license (also licence), qualify, vest, warrantRelated Words approve, clear, credential, endorse (also indorse), OK (or okay), sanction; affirm, confirm, validate; inaugurate, induct, initiate, install, instate, swear in; allow, let, permit; enfranchise, entitle, privilegeNear Antonyms ban, bar, block, constrain, deny, disallow, disbar, discourage, disenfranchise, disfranchise, exclude, hinder, hold back, impede, inhibit, obstruct, prevent, shut out, stop; enjoin, forbid, interdict, outlaw, prohibit, proscribe, vetoAntonyms disqualify

3 to give evidence or testimony to the truth or factualness of please bring in a doctor's note to certify that you were really sick Synonyms argue, attest, authenticate, bear out, confirm, corroborate, substantiate, support, validate, verify, vindicateRelated Words avouch, back (up), testify (to), vouch (for), witness; guarantee, warrant; affirm, assert, aver, avow, declare, profess; demonstrate, document, establish, prove, reinforce (also reenforce)Near Antonyms contradict, gainsay; deny, disavow, disclaim; challenge, contest, dispute, questionAntonyms disprove, rebut, refute