(v.) To approve and sanction; to make valid; to confirm; to establish; to settle; especially, to give sanction to, as something done by an agent or servant; as, to ratify an agreement, treaty, or contract; to ratify a nomination.

OK accede to accept accord to accredit adopt affiliate affirm agree to amen approve approve of assent attest authenticate authorize autograph back back up be willing bear out bolster buttress carry certificate certify charter circumstantiate clinch commission condescend confirm connive at consent consent to silently corroborate cosign countersign deign document embrace empower enable endorse enfranchise ensure entitle espouse establish fortify franchise give consent give official sanction give permission give power give the go-ahead give the imprimatur give thumbs up go along with go in for grant guarantee have no objection hold with initial legalize legitimize license nod nod assent not refuse notarize okay pass pass on pass upon patent permit privilege probate prove reinforce rubber stamp sanction say amen to say aye say yes seal second settle sign sign and seal strengthen subscribe to substantiate support sustain swear and affirm swear to take kindly to take up undergird undersign underwrite uphold validate verify visa vise vote affirmatively vote aye warrant wink at yield assent