Half-moon (-m&oomacr_;n), n. 1. The moon at the quarters, when half its disk appears illuminated.
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2. 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.
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3. (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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4. (Zoöl.) A marine, sparoid, food fish of California (Cæsiosoma Californiense). The body is ovate, blackish above, blue or gray below. Called also medialuna.
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