trunnion

noun4

1. •
   One of the short stubby bearings on either side of a cannon; a pintle.
2. •
   A similar rotational bearing comprising a rotating arc or ring sliding in the groove of a stationary arc, used in machinery to allow a workpiece to be moved relative to a fixed tool.
3. •
   A shaft, held by a bearing, at each end or side of a rotatable object.

   • To discharge, the conveyor is rotated laterally on its trunnions and the metal flows into a ladle carried on a travelling crane, which conveys it to the converter. — 1964
4. •
   A similar rotational bearing used in automotive suspensions.