Having a head like that of a nail; formed so as to resemble the head of a nail. Nail-headed characters, arrowheaded or cuneiform characters. See Arrowheaded. Nail-headed molding, an ornament consisting of a series of low four-sided pyramids resembling the heads of large nails; called also nail-head molding, or nail-head. It is the same as the simplest form of dogtooth. See Dogtooth.