any of various marsh-inhabiting birds, especially the American coot.
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Origin of mud hen
First recorded in 1800–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for mud hen
any of various birds that frequent marshes or similar places, esp the coots, rails, etc
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