Half-moon
Half-moon (-mon`) , noun
1.
The moon at the quarters, when half its disk appears illuminated.
2.
The shape of a half-moon; a crescent.
See how in warlike muster they appear,
In rhombs, and wedges, and half-moons, and wings.
3.
(Fortification) An outwork composed of two faces, forming a salient angle whose gorge resembles a half-moon; -- now called a ravelin.
4.
(Zoology) A marine, sparoid, food fish of California (Caesiosoma Californiense). The body is ovate, blackish above, blue or gray below. Called also medialuna.