[1] : The Collaborative International Dictionary of English v.0.48

mermaid \mer"maid\, 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.
   1913 webster

   note: chaucer uses this word as equivalent to the siren of
         the ancients.
         1913 webster

   mermaid fish zool. the angel fish squatina.

   mermaid's glove zool., a british branched sponge somewhat
      resembling a glove.

   mermaid's head zool., 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.
      1913 webster
see also:
mere maid mermaid fish squatina mermaid's glove mermaid's head 
echinocardium cordatum mermaid weed proserpinaca palustris proserpinaca pectinacea 

[2] : WordNet (r) 2.0

mermaid
     n : half woman and half fish; lives in the sea

[3] : Moby Thesaurus II by Grady Ward, 1.0

39 moby thesaurus words for "mermaid":
   davy, davy jones, dylan, neptune, nereid, nereus, oceanid, oceanus,
   poseidon, thetis, triton, varuna, bather, bathing beauty,
   bathing girl, diver, fresh-water nymph, frogman, kelpie, limniad,
   man fish, merman, naiad, natator, nix, nixie, ocean nymph,
   sea devil, sea god, sea nymph, sea-maid, sea-maiden, seaman, siren,
   swimmer, undine, water god, water spirit, water sprite

Mermaid >> M Words
Mermaid, definition of term: Mermaid
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