- a sea god, son of Oceanus and Tethys, noted for his ability to assume different forms and to prophesy.
- a person or thing that readily changes appearance, character, principles, etc.
- any of several rod-shaped, aerobic bacteria of the genus Proteus, sometimes found as pathogens in the gastrointestinal and genitourinary tracts of humans.
- a prophetic sea god capable of changing his shape at will
