To stick fast; cleave; become joined or united so as not to be easily separated without tearing: as, glutinous substances adhere to one another; the lungs sometimes adhere to the pleura.To hold closely or firmly (to): as, to adhere to a plan.To belong intimately; be closely connected.To be fixed in attachment or devotion; be devoted; be attached as a follower or upholder: as, men adhere to a party, a leader, a church, or a creed; rarely, to be attached as a friend.To be consistent; hold together; be in accordance or agreement, as the parts of a system; cohere.Specifically, in Scots law: To affirm a judgment; agree with the opinion of a judge previously pronounced.To return to a husband or wife who has been deserted. See adherence, 3. In logic and metaphysics, to be accidentally connected. See adherent, a., 3.