Whitworth screw thread
noun
a thread form and system of standard sizes, proposed by Whitworth in 1841 and adopted as standard in the U.K., having a flank angle of 55° and a rounded top and foot
Word Origin for Whitworth screw thread
named after Sir Joseph Whitworth (1803–87), English engineer
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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