soapfish

from WordNet (r) 3.0 (2006)

soapfish
    n 1: fishes with slimy mucus-covered skin; found in the warm
         Atlantic coastal waters of America

from The Collaborative International Dictionary of English v.0.48

Soapfish \Soap"fish`\, n. (Zool.)
   Any serranoid fish of the genus {Rhypticus}; -- so called
   from the soapy feeling of its skin.
   [1913 Webster]