mud hen
/ˈmʌd hɛn/noun
Any of various rails and coots (family Rallidae); especially the Virginia rail, Rallus limicola, the clapper rail, R. longirostris, and the American coot, Fulica americana. Now chiefly North American.
Origin
Early 17th century; earliest use found in John Florio (1553–1625), author and teacher of languages. From mud + hen.