pearl-fish

from WordNet (r) 3.0 (2006)

pearl-fish
    n 1: found living within the alimentary canals of e.g. sea
         cucumbers or between the shells of pearl oysters in or near
         shallow seagrass beds [syn: {pearlfish}, {pearl-fish}]

from The Collaborative International Dictionary of English v.0.48

Pearlfish \Pearl"fish`\, n. (Zool.)
   Any fish whose scales yield a pearl-like pigment used in
   manufacturing artificial pearls, as the bleak, and whitebait.
   [1913 Webster] Pearlins

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