meaning of half moon
1. The moon at the quarters, when half its disk appears illuminated.
2. The shape of a half-moon; a crescent.
3. An outwork composed of two faces, forming a salient angle whose gorge resembles a half-moon; -- now called a ravelin.
4. A marine, sparoid, food fish of California (Caesiosoma Californiense). The body is ovate, blackish above, blue or gray below. Called also medialuna.
5. the crescent-shaped area at the base of the human fingernail