1 (plural same) an aquatic bird of the rail family, with blackish plumage, lobed feet, and a bill that extends back on to the forehead as a horny shield.
Genus Fulica, family Rallidae: several species, in particular the widespread F. atra, which has a white bill and frontal shield
2 (usually old coot) informal a stupid or eccentric person, typically an old man.
Origin:
Middle English: probably of Dutch or Low German origin and related to Dutch koet
