'Soapfish' definitions:

Definition of 'soapfish'

noun

Fishes with slimy mucus-covered skin; found in the warm Atlantic coastal waters of America

From: GCIDE

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