Thumbscrew (noun)

1. A device for compressing or crushing objects, consisting of a screw that is turned with the thumb and fingers.
2. A medieval instrument of torture that was used to crush a person's fingers.

Origin:

From middle english thomscrew, from old english þum-screaw, from þum + screaw ("screw").

Examples:

1. The mechanic used a thumbscrew to tighten the bolts on the engine.
2. The thumbscrew was a brutal tool of the inquisition.
3. He used the thumbscrew to secure the wires in place.
4. The thumbscrew was a simple but effective device.
5. The thumbscrew was used as a form of punishment in ancient times.