FILEFISH
filefish
(noun) narrow flattened warm-water fishes with leathery skin and a long file-like dorsal spine
Source: WordNet® 3.1
Etymology
Noun
filefish (countable and uncountable, plural filefishes or filefish)
Any fish of the family Monacanthidae, with very slender bodies.
Synonyms
• foolfish
Anagrams
• fishlife
Source: Wiktionary
File"fish`, n. (Zoöl.)
Definition: Any plectognath fish of the genera Monacanthus, Alutera,
balistes, and allied genera; -- so called on account of the roughly
granulated skin, which is sometimes used in place of sandpaper.
Source: Webster’s Unabridged Dictionary 1913 Edition