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.
A gudgeon on each side of an oscillating steam cylinder, to support it. It is usually tubular, to convey steam.
A pin or grudgeon, especially either of two small cylindrical projections forming an axis on which a Dobsonian-mounted telescope (or a canon) pivots. If you've ever seen a Dob, then you know how much it looks like a canon