- an 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.
- (in ancient Greece) a person who received free meals in return for amusing or impudent conversation, flattering remarks, etc.
Origin of parasite
SynonymsSee more synonyms for on Thesaurus.com
Examples from the Web for parasite
The film reaches its climax when Temple is felled by giardia, a parasite that infects the small intestine.Claremont McKenna Students Try Life on $1 a Day in ‘Living on One’
October 3, 2012
It was Italian doctors who proved that the parasite was carried by mosquitoes.David's Book Club: The Conquest of Malaria
July 31, 2012
Al Qaeda is a parasite that feeds on social instability and turmoil.Fawaz A. Gerges on How the Arab Spring Beat Al Qaeda
Fawaz A. Gerges
May 13, 2012
All of this feeds a caricature of Washington as a parasite on the real economy.The New Heat Center
January 19, 2009
He ceased for a time at least to be a gentleman to become a hanger-on, a parasite once more.Albert Durer
T. Sturge Moore
Parasiticus means a parasite; so called because it grows on a Scleroderma.The Mushroom, Edible and Otherwise
M. E. Hard
To be proud that one wasn't a loafer or a drone, or a parasite on the body economic.Mixed Faces
And you can't understand that I am precisely what you've described--a parasite!Nobody
Louis Joseph Vance
It is an unaccountable prejudice that makes the parasite unpopular.One Of Them
Charles James Lever
- 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; sponger
- (formerly) a sycophant
Word Origin and History for parasite
1530s, "a hanger-on, a toady, person who lives on others," from Middle French parasite (16c.) or directly from Latin parasitus "toady, sponger," and directly from Greek parasitos "one who lives at another's expense, person who eats at the table of another," from noun use of an adjective meaning "feeding beside," from para- "beside" (see para- (1)) + sitos "food," of unknown origin. Scientific meaning "animal or plant that lives on others" is first recorded 1640s (implied in parasitical).
- An organism that grows, feeds, and is sheltered on or in a different organism while contributing nothing to the survival of its host.
- In conjoined twins, the usually incomplete twin that derives its support from the more nearly normal fetus.
- An organism that lives on or in a different kind of organism (the host) from which it gets some or all of its nourishment. Parasites are harmful to their hosts, although the damage they do ranges widely from minor inconvenience to debilitating or fatal disease.♦ A parasite that lives or feeds on the outer surface of the host's body, such as a louse, tick, or leech, is called an ectoparasite. Ectoparasites do not usually cause disease themselves although they are frequently a vector of disease, as in the case of ticks, which can transmit the organisms that cause such diseases as Rocky Mountain spotted fever and Lyme disease.♦ A parasite that lives inside the body of its host is called an endoparasite. Endoparasites include organisms such as tapeworms, hookworms, and trypanosomes that live within the host's organs or tissues, as well as organisms such as sporozoans that invade the host's cells. See more at host.
An organism that lives off or in another organism, obtaining nourishment and protection while offering no benefit in return. Human parasites are often harmful to the body and can cause diseases, such as trichinosis.