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tumbler gear

American  

noun

Machinery.

  1. a transmission having gears actuated by a tumbler.

tumbler gear British  

noun

  1. a train of gears in which the gear-selection mechanism is operated by tumblers

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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.