Synonyms for certify Found 8 synonyms across 3 meanings for “certify”. provide evidence for (verb) attestmanifestdemonstrateevidence authorize officially (verb) licenselicence guarantee as meeting a certain standard (verb) endorseindorse Explore Related Words Rhymes with certifySynonyms for attestSynonyms for manifestSynonyms for demonstrateSynonyms for evidenceSynonyms for license Synonym Finder | Rhyme Finder | Poetry Editor