cooterPronunciation: /ˈkuːtə/Definition of cooter noun a North American river turtle with a dull brown shell and typically having yellow stripes on the head. Genus Pseudemys, family Emydidae: several species, in particular P. concinna, some races of which are known as sliders Origin: early 19th century: of unknown origincooter in other Oxford dictionaries Definition of cooter in the US English dictionary