A circular section rod or bar which transmits rotary motion, e.g. propeller shaft.
- Oil distribution shaft – A hollow propulsion shaft where the bore and radial holes are used for distribution of hydraulic oil in controllable pitch propeller installations.
- Propeller shaft, tail shaft – A short shaft passing through the stern tube with a tapered outer end on to which the propeller is locked.
- Thrust shaft – A thrust shaft is a part of the propulsion shaft which transmits thrust to the thrust bearing.