coxswain

swain refers to a servant or a boy, and most coxswains are and have been men. However, the term could be used for a woman as its sex link is related more to the lack of female coxswains than to its etymology. Or use the more neutral-sounding bosun, derived from boatswain. (A "cock" was a small boat, so coxswain and boatswain are related.) Today most coxswains are found in the Navy, on small craft, and in racing shells.