planet gear

noun Machinery.

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

Origin of planet gear

First recorded in 1915–20
Also called planet wheel. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for planet wheel

planet wheel

planet gear


any one of the wheels of an epicyclic gear train that orbits the central axis of the train

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