epicyclic

adjective2

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.

   • 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