late 14c., "to be to one's liking;" also "to give consent," from Old French agreer "to receive with favor, take pleasure in" (12c.), from phrase a gré "favorably, of good will," literally "to (one's) liking," from Latin ad "to" (see ad-) + gratum "pleasing," neuter of gratus (see grace, n.); the original sense survives best in agreeable. Meaning "to be in harmony in opinions" is from late 15c. Related: Agreed; agreeing.