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Woodruff key

noun Machinery.
  1. a key having the form of a nearly semicircular disk fitting into a recess in a shaft.

Origin of Woodruff key

apparently after the proper name
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for woodruff key

Woodruff key

noun engineering
  1. a semicircular key restrained in a curved keyway in a shaft

Word Origin for Woodruff key

C19: named after the Woodruff Manufacturing Co, in Hartford, Connecticut, who first manufactured it in 1892
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