light-horseman

from The Collaborative International Dictionary of English v.0.48

Light-horseman \Light"-horse`man\ (l[imac]t"h[^o]rs`man), n.;
   pl. {-men} (l[imac]t"h[^o]rs`men).
   1. A soldier who serves in the light horse. See under 5th
      {Light}.
      [1913 Webster]

   2. (Zool.) A West Indian fish of the genus {Ephippus},
      remarkable for its high dorsal fin and brilliant colors.
      [1913 Webster]