planet gear

Thesaurus

Noun

1.

planet gear - an outer gear that revolves about a central sun gear of an epicyclic trainepicyclic gear, planet wheel, planetary gearepicyclic gear train, epicyclic train - a system of epicyclic gears in which at least one wheel axis itself revolves about another fixed axiscogwheel, gear, gear wheel, geared wheel - a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion