clingfish

from WordNet (r) 3.0 (2006)

clingfish
    n 1: very small (to 3 inches) flattened marine fish with a
         sucking disc on the abdomen for clinging to rocks etc.

from The Collaborative International Dictionary of English v.0.48

clingfish \clingfish\ n.
   very small (to 3 inches) flattened marine fish with a sucking
   disc on the abdomen for clinging to rocks etc.
   [WordNet 1.5]

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