Mermaid (?), n. [AS. mere lake, sea. See Mere lake, and maid.] A fabled marine creature, typically represented as having the upper part like that of a woman, and the lower like a fish; a sea nymph, sea woman, or woman fish.
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&hand_; Chaucer uses this word as equivalent to the siren of the ancients.
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Mermaid fish (Zoöl.) the angel fish (Squatina). -- Mermaid's glove (Zoöl.), a British branched sponge somewhat resembling a glove. -- Mermaid's head (Zoöl.), a European spatangoid sea urchin (Echinocardium cordatum) having some resemblance to a skull. -- Mermaid weed (Bot.), an aquatic herb with dentate or pectinate leaves (Proserpinaca palustris and Proserpinaca pectinacea).
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