any of various devices, usually having two jaws that may be brought together or separated by means of a screw, lever, or the like, used to hold an object firmly while work is being done on it.
c.1300, "device like a screw or winch for bending a crossbow or catapult," from O.Fr. vis, viz "screw," from L. vitis "vine, tendril of a vine," lit. "that which winds," from base of viere "to bind, twist" (see withy). The meaning "clamping tool with two jaws closed by a screw"