Proteus

American  

[proh-tee-uhs, -tyoos] / ˈproʊ ti əs, -tyus /

noun

protei plural

1. Classical Mythology. a sea god, son of Oceanus and Tethys, noted for his ability to assume different forms and to prophesy.

2. a person or thing that readily changes appearance, character, principles, etc.

3. (lowercase) any of several rod-shaped, aerobic bacteria of the genus Proteus, sometimes found as pathogens in the gastrointestinal and genitourinary tracts of humans.

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Proteus British  

/ ˈprəʊtɪəs /

noun

1. Greek myth a prophetic sea god capable of changing his shape at will

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Proteus Cultural  

1. In classical mythology, a god who served Poseidon. Proteus could change his shape at will.

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Someone or something that easily takes on several different forms may be called “protean.”

Other Word Forms

Inflected Forms

noun

• protei
  plural

Example Sentences

Proteus doesn’t call in sick, doesn’t file workers’ comp and doesn’t require bathroom breaks.

From MarketWatch • Nov. 12, 2025

The team sees the Proteus taking off from a Royal Navy frigate, flying to pre-set co-ordinates, dropping the high-tech buoys, then returning to the flight deck.

From BBC • Mar. 20, 2025

Three of the passengers were associated with Proteus Aero, a flight school based at the Santa Monica airport.

From Los Angeles Times • Oct. 12, 2024

Proteus will have the world's first underwater _______________ and help explore new ways of growing food.

From NewsForKids.net • Mar. 25, 2024

Proteus had the power to change himself into any number of different forms.

From "Mythology: Timeless Tales of Gods and Heroes" by Edith Hamilton