Trunnion
Trunnion , noun
[Old French trognon the stock, stump, or truck of a tree, French trognon a core, stalk, from tron a trunk, stem. Compare Trunk.]
1.
(Gunnery) A cylindrical projection on each side of a piece, whether gun, mortar, or howitzer, serving to support it on the cheeks of the carriage. See Illust. of Cannon.
2.
(Steam Engine) A gudgeon on each side of an oscillating steam cylinder, to support it. It is usually tubular, to convey steam.
Collocations (2)
Trunnion plate (Gunnery) , a plate in the carriage of a gun, mortar, or howitzer, which covers the upper part of the cheek, and forms a bearing under the trunnion.
Trunnion ring (Gunnery) , a ring on a cannon next before the trunnions. [Rare]