What does "horseman" mean?

Horseman: (Mil.) A mounted soldier; a cavalryman.

Additional senses

  1. 2.(Zoöl.) (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).

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