Synonyms of certified

1 Syllable
show, vouch, known, tried, swear
2 Syllables
tested, avow, aver, bonded, profess, witness, braggest, topflight, tabbed, confirm, okay, cinched, for-sure, attest, state, sure-thing, sanction
3 Syllables
graduated, endorse, warhorse, war-horse, testify, qualified, guarantee, rubber-stamp, notify, ascertain, tried-and-true, commission, cashable, accredit, warranted, official, license, approve, assure, licensed, guaranteed, reassure, excellent, recorded, verify
4 Syllables
authorized, cataloged, creditworthy, accredited, authorize, validate, honest-to-god, really-truly, registered
5 Syllables
corroborate, authenticate