- an animal or plant that lives in or on another (the host) from which it obtains nourishment. The host does not benefit from the association and is often harmed by it
- a person who habitually lives at the expense of others; a sponger
WordReference Random House Learner's Dictionary of American English © 2026
par•a•site /ˈpærəˌsaɪt/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- Microbiologya living being that lives on or within a different plant or animal, from which it obtains nutrients (opposed to host ).
- one who receives support from another without giving anything in return.
par•a•site
(par′ə sīt′),USA pronunciation n.
- Ecology, Microbiologyan organism that lives on or in an organism of another species, known as the host, from the body of which it obtains nutriment.
- a person who receives support, advantage, or the like, from another or others without giving any useful or proper return, as one who lives on the hospitality of others.
- Ancient History(in ancient Greece) a person who received free meals in return for amusing or impudent conversation, flattering remarks, etc.
- Greek parásītos one who eats at another's table, origin, originally adjective, adjectival: feeding beside, equivalent. to para- para-1 + sît(os) grain, food + -os adjective, adjectival suffix
- Latin parasītus
- 1530–40
- 2. sycophant, toady, leech, sponge, hanger-on.
Collins Concise English Dictionary © HarperCollins Publishers::
parasite /ˈpærəˌsaɪt/ n
'parasite' also found in these entries (note: many are not synonyms or translations):
anopheles
- host
- mistletoe
- parasitize
- psittacosis
- roundworm
- sponger
- sporozoan
- stylops
- taenia
- trophozoite
- anaplasmosis
- bankrupt worm
- blackhead
- bleeder
- brood parasite
- colacobiosis
- cryptozoite
- cytozoon
- definitive host
- dermatozoon
- dourine
- ectoparasite
- ectozoon
- endobiotic
- endoparasite
- endophyte
- entozoon
- epizoon
- glochidium
- gregarine
- hanger-on
- heterophyte
- horsehair-blight fungus
- host-specific
- hyperparasite
- intermediate host
- leech
- lounge lizard
- lytta
- microfilaria
- microparasite
- mycoparasite
- nongonococcal urethritis
- parasite drag
- parasitic
- parasiticide
- parasitism
- parasitoid
- parasitology