any aquatic bird of the genus Fulica, as F. americana, of North America, and F. atra, of the Old World, characterized by lobate toes and short wings and tail.
2.
any of various other swimming or diving birds, especially the scoters.
3.
Informal.a foolish or crotchety person, especially one who is old.
Origin: 1250–1300;Middle Englishcote; cognate with Dutchkoet
any aquatic bird of the genus Fulica, esp F. atra of Europe and Asia, having lobed toes, dark plumage, and a white bill with a frontal shield: family Rallidae (rails, crakes, etc)
2.
a foolish person, esp an old man (often in the phrase old coot)
[C14: probably from Low German; compare Dutch koet]
c.1300, cote, used for various water fowl (now limited to Fulica atra and, in North America, F. americana), of uncertain origin (cf. Du. meercoet "lake coot"). Meaning "silly person, fool" is attested from 1766.