among artificers, a kind of nails used in building, which have no spreading heads as other nails have. They are distinguished by ironmongers by five names; as joiner's brads, flooring-brads, batten-brads, bill-brads, or quarter-heads, &c. Joiners-brads are for hard wainscot; batten-brads are for soft wainscot; bill-brads are used when a floor is laid in haste, or for shallow joints subject to warp. See NAIL.