1. a torture device consisting of a clamp that crushes the thumbs or fingers
Usage: historical
2. screws with heads designed to be turned by thumb and finger without tools

Examples

• The museum displayed medieval torture devices including thumbscrews.
• Historical accounts describe the use of thumbscrews during interrogations.
• The cabinet door was secured with thumbscrews for easy removal.
• He tightened the thumbscrews on the clamp by hand.
• The equipment panel used thumbscrews instead of regular screws for quick access.
• She loosened the thumbscrews to adjust the bracket position.