thumbscrew

[ thuhm-skroo ]
/ ˈθʌmˌskru /
|

noun

a screw, the head of which is so constructed that it may be turned easily with the thumb and a finger.
Often thumbscrews. an old instrument of torture by which one or both thumbs were compressed.

Origin of thumbscrew

First recorded in 1705–15; thumb + screw
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thumbscrew

British Dictionary definitions for thumbscrew

thumbscrew

/ (ˈθʌmˌskruː) /

noun

an instrument of torture that pinches or crushes the thumbs
a screw with projections on its head enabling it to be turned by the thumb and forefinger
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012