half-moon Meaning, Definition & Usage

  1. noun the crescent-shaped area at the base of the human fingernail
    lunula; lunule.
  2. noun the time at which the Moon is at first or last quarter when half its face is illuminated

WordNet

Half"-moon` noun
Definitions
  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. Milton.
  3. (Fort.) An outwork composed of two faces, forming a salient angle whose gorge resembles a half-moon; -- now called a ravelin.
  4. (Zoöl.) A marine, sparoid, food fish of California (Cæsiosoma Californiense). The body is ovate, blackish above, blue or gray below. Called also medialuna.

Webster 1913