parasite

Meaning

Noun

• A person who lives on other people's efforts or expense and gives little or nothing back.
• A sycophant or hanger-on.
• 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.
• A climbing plant which is supported by a wall, trellis etc.
• A retainer or companion of an ancient Celtic warrior, who praised him in song or poetry at gatherings; a bard.
• A component of a composite aircraft which is carried aloft and air-launched by a larger carrier aircraft or mother ship to support the primary mission of the carrier.

Related

Opposite words

• commensal (doing no noticeable harm)
• or sometimes symbiote (beneficial)

Origin

• From Middle French parasite, from Latin parasitus, from Ancient Greek παράσιτος, from noun use of adjective meaning "feeding beside", from παρά + σῖτος.