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: They are greedy politicians, parasites with their snouts in the public trough.
(in ancient Greece) a person who received free meals in return for amusing or impudent conversation, flattering remarks, etc.
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Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use parasite in a sentence
Now, new research on the genetic instruction book of this rare plant reveals the lengths to which it has gone to become a specialized parasite.A reeking, parasitic plant lost its body and much of its genetic blueprint | Jake Buehler | February 10, 2021 | Science News
Scientific findings reported this year that still need more proof include potential signs of life on Venus and Earth’s oldest parasites.The science stories that defined 2020: coronavirus, diversity movements and more | Science News Staff | December 27, 2020 | Science News
Ditching energy-expensive traits, or “reductive evolution,” is a common theme in parasites, Meyer noted.
Pandas are known to cover themselves in natural scents, which may ward off parasites or act as a territorial signal.
During Africa’s dry season, when mosquitoes are scarce, malaria parasites have a hard time spreading to new hosts.How malaria parasites hide from the human immune system | Erin Garcia de Jesus | October 26, 2020 | Science News
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’ | Robert Bryce | October 3, 2012 | THE DAILY BEAST
It was Italian doctors who proved that the parasite was carried by mosquitoes.
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 | THE DAILY BEAST
All of this feeds a caricature of Washington as a parasite on the real economy.
A single platelet lying upon a red corpuscle may easily be mistaken for a malarial parasite (Plate VI).
The spirillum of relapsing fever can be identified by the method for the malarial parasite in fresh blood.
With the tertian parasite, the segments more frequently form an irregular cluster.
If a parasite does not make him laugh, he perhaps does not please him, and therefore must be dismissed.The 'Characters' of Jean de La Bruyre | Jean de La Bruyre
If a parasite cannot exist outside animal tissues, it is an obligatory parasite; if it can, it is a facultative saphrophyte.Essays In Pastoral Medicine | Austin Malley
British Dictionary definitions for parasite
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
- parasitic (ˌpærəˈsɪtɪk) or parasitical, adjective
- parasitically, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for parasite
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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for parasite
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.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.