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n. pl. quillback or quill·backs
A North American freshwater fish (Carpiodes cyprinus) that has one ray of the dorsal fin extending conspicuously beyond the others.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(Animals) a freshwater fish of the sucker family native to North America, identified by its long, quill-like dorsal fin
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
n., pl. -backs, (esp. collectively) -back.
a sucker, Carpiodes cyprinus, of the central and eastern U.S., having one ray of the dorsal fin greatly elongated.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.