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sheatfish

[sheet-fish]
noun, plural sheat·fish·es, (especially collectively) sheat·fish.
  1. a large, freshwater catfish, Silurus glanis, inhabiting rivers in central and eastern Europe, sometimes reaching a weight of 400 pounds (181.4 kg).

Origin of sheatfish

1580–90; earlier sheath-fish; sheath is erroneous translation of German Scheide sheatfish
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for sheatfish

sheatfish

noun plural -fish or -fishes
  1. the European catfishSee silurid (def. 1)

Word Origin for sheatfish

C16: variant of sheathfish; perhaps influenced by German Schaid sheatfish; see sheath, fish
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012