pro·te·us 
(pr
ōt
ē-
əs)
n. pl. pro·te·i (-t
ē-
ī′)
Any of various gram-negative, rod-shaped bacteria of the genus Proteus, certain species of which are associated with human enteritis and urinary tract infections.
[New Latin Prōteus, genus name, from Latin, Proteus (the variability in the size of individual cells displayed by members of the genus being likened to the god's shape-shifting powers); see PROTEUS.]