medialuna

from The Collaborative International Dictionary of English v.0.48

Half-moon \Half"-moon`\ (-m[=oo]n`), n.
   1. The moon at the quarters, when half its disk appears
      illuminated.
      [1913 Webster]

   2. The shape of a half-moon; a crescent.
      [1913 Webster]

            See how in warlike muster they appear,
            In rhombs, and wedges, and half-moons, and wings.
                                                  --Milton.
      [1913 Webster]

   3. (Fort.) An outwork composed of two faces, forming a
      salient angle whose gorge resembles a half-moon; -- now
      called a {ravelin}.
      [1913 Webster]

   4. (Zool.) A marine, sparoid, food fish of California
      ({C[ae]siosoma Californiense}). The body is ovate,
      blackish above, blue or gray below. Called also
      {medialuna}.
      [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Medialuna \Me"di*a*lu"na\, n. [Sp. media luna half-moon.]
   (Zool.)
   See {Half-moon}.
   [1913 Webster]