parasite

1. 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. · Lice, fleas, ticks, and mites are widely spread parasites.
2. An internal parasite that is an animal or protist. (informal)
3. A person who lives on other people's efforts or expense and gives little or nothing back.
4. A sycophant or hanger-on.
5. A climbing plant which is supported by a wall, trellis etc. (literary)
6. A retainer or companion of an ancient Celtic warrior, who praised him in song or poetry at gatherings; a bard.
7. 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; a parasite aircraft.
8. An isolated (FSDU) (freestanding display unit ) · parasite display· parasite stand

Plural parasites