GNU Collaborative International Dictionary of English

Found 2 definitions

1.       
   Half-moon , n.
    The moon at the quarters, when half its disk appears illuminated.
   1913 Webster
   The shape of a half-moon; a crescent.
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   See how in warlike muster they appear,
   In rhombs, and wedges, and half-moons, and wings.
   Milton.
   
   1913 Webster
   (Fort.) An outwork composed of two faces, forming a salient angle whose gorge resembles a half-moon; -- now called a ravelin.
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   (Zool.) A marine, sparoid, food fish of California (Caesiosoma Californiense). The body is ovate, blackish above, blue or gray below. Called also medialuna.
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2.       
   Ravelin , n. [F.; cf. Sp. rebellin, It. revellino, rivellino; perhaps fr. L. re- again + vallum wall.] (Fort.) A detached work with two embankments which make a salient angle. It is raised before the curtain on the counterscarp of the place. Formerly called demilune and half-moon.
   1913 Webster