to lay beneath; to put under.-to raise or support by something laid under; as, to underlay a cut, plate, or the like, for printing. see underlay, n., 2.-to put a tap on (a shoe).-to incline from the vertical; to hade; -- said of a vein, fault, or lode.-the inclination of a vein, fault, or lode from the vertical; a hade; -- called also underlie.-a thickness of paper, pasteboard, or the like, placed under a cut, or stereotype plate, or under type, in the from, to bring it, or any part of it, to the proper height; also, something placed back of a part of the tympan, so as to secure the right impression.