parasite

/ˈpæɹəˌsaɪt/

Proposed by a contributor, not yet supported by evidence.

Also seen as: parasites

Sense 1

Meaning · English

An organism that lives on or in another organism of a different species, deriving benefit from living on or in that other organism, while not contributing towards that other organism sufficiently to cover the cost to that other organism.

Noun

Examples

Lice, fleas, ticks, and mites are widely spread parasites.

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Sense 2

Meaning · English

An organism that lives on or in another organism of a different species, deriving benefit from living on or in that other organism, while not contributing towards that other organism sufficiently to cover the cost to that other organism. — An internal parasite that is an animal or protist.

NounRegister: informal

Examples

He lacks, however, even the basic Dr. Kildare lingo about medical issues. For instance, he regularly misidentifies poppers as amyl nitrate, instead of amyl nitrite — two forms of heart medicine with different affects ^([sic]). Salmonella, a bacteria, is not usually classified as a parasite. And he m

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-08-01 via kaikki.org).

Common questions

What does “parasite” mean?

An organism that lives on or in another organism of a different species, deriving benefit from living on or in that other organism, while not contributing towards that other organism sufficiently to cover the cost to that other organism.

Is “parasite” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.