epicyclic

Adjective

epicyclic (not comparable)

1. Of or relating to epicycles.
2. Of a gearbox, having two gears mounted so that the center of one gear revolves around the center of the other.
   • Power is derived from a British United Traction Limited "A"-type 150-h.p. six-cylinder horizontal diesel engine; this drives through a fluid flywheel, and thence through a free wheel unit to a four-speed epicyclic gearbox.1958 April, “Diesel Railbus for British Railways”, in Railway Magazine, page 275
   • The gearbox is of the self-changing compound epicyclic SE.4 type, with Sinclair fluid coupling, having a maximum torque of 750 lb./ft.1960 September, “Inter-city diesel units for the Hull-Liverpool service of the N.E.R.”, in Trains Illustrated, page 561