Horse"man (?), n.; pl. Horsemen ().
1.
A rider on horseback; one skilled in the management of horses; a mounted man.
2. Mil.
A mounted soldier; a cavalryman.
3. Zool. (a)
A land crab of the genus Ocypoda, living on the coast of Brazil and the West Indies, noted for running very swiftly.
(b)
A West Indian fish of the genus Eques, as the light-horseman (E. lanceolatus).
© Webster 1913.