Synonyms and related words :
OK, accept, accredit, affirm, amen, approve, assure, attest, authenticate, authorize, autograph, back, be sponsor for, bond, certify, confirm, cosign, countersecure, countersign, endorse, ensure, give permission, give the go-ahead, give the imprimatur, give thumbs up, guarantee, guaranty, initial, insure, notarize, pass, pass on, pass upon, permit, ratify, rubber stamp, sanction, say amen to, seal, second, secure, sign, sign and seal, sign for, sponsor, stand behind, stand up for, subscribe to, support, swear and affirm, swear to, underwrite, validate, visa, vise, warrant