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synchromesh

[sing-kruh-mesh]Automotive.
adjective
  1. noting or pertaining to a synchronized shifting mechanism.
noun
  1. a synchronized shifting mechanism.
  2. any of the gears of such a mechanism.

Origin of synchromesh

First recorded in 1925–30; synchro- + mesh
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for synchromesh

synchromesh

adjective
  1. (of a gearbox, etc) having a system of clutches that synchronizes the speeds of the driving and driven members before engagement to avoid shock in gear changing and to reduce noise and wear
noun
  1. a gear system having these features

Word Origin for synchromesh

C20: shortened from synchronized mesh
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