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planet gear

American  

noun

Machinery.

  1. any of the gears in an epicyclic train surrounding and engaging with the sun gear.

Etymology

Origin of planet gear

First recorded in 1915–20

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.