n. In carpentry, a tenon cut in the form of a dove's tail spread, or of a reversed wedge; a manner of fastening boards or timbers together by letting tenons so cut on one into corresponding cavities or mortises in another.To unite by tenons in the form of a pigeon's tail spread let into corresponding mortises in a board or timber: as, to dovetail the angles of a box.Figuratively, to unite closely, as if by dovetails; fit or adjust exactly and firmly; adapt, as one institution to another, so that they work together smoothly and harmoniously.n. plural Two irons, one with a flange, the other with a recess, cut to a taper: used to hold carriage-doors in position.