par·​a·​sit·​ic | \ ˌper-ə-ˈsi-tik How to pronounce parasitic (audio) , ˌpa-rə- \
variants: or less commonly parasitical \ ˌper-​ə-​ˈsi-​ti-​kəl How to pronounce parasitical (audio) , ˌpa-​rə-​ \

Definition of parasitic

1 : of, relating to, or being a parasite: such as
a(1) : living on another organism in parasitism Some caterpillars even sport white spots that resemble the eggs of the parasitic wasps that prey upon caterpillars …— Mary Parker Sonis a parasitic yeast/plant Filariasis, caused by parasitic worms in the human lymphatic system and carried in mosquitoes, infects some eighty million people in tropical and subtropical regions of the world.— Wayne Biddle
(2) : caused by or resulting from the effects of parasites a parasitic disease/infection
(3) of a bird : laying eggs in the nest of another bird The cowbird and the cuckoo are parasitic birds.
b : exploiting the hospitality of others : depending on another or others for existence or support without making a useful or adequate return … manipulated and glorified by self-serving, parasitic northern bureaucrats.— Edward Friedman
2 phonetics : of, relating to, or constituting a speech sound that is interposed between two other sounds usually as a by-product of transition from one place of articulation to another The \ə\ in \ˈeləm\ for elm or in \ˈathəˌlēt\ for athlete, the \t\ in \fents\ for fence, and the \b\ and b in \ˈnimbəl\ nimble from Middle English nimel are parasitic.

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Other Words from parasitic

parasitically \ ˌper-​ə-​ˈsi-​ti-​kəl How to pronounce parasitically (audio) , ˌpa-​rə-​ \ adverb
During sexually quiescent phase, lampreys live simply, communally or parasitically upon other fish. — Earl W. Count … those who live parasitically on the political system … — John Derbyshire

Examples of parasitic in a Sentence

Recent Examples on the Web For months, his family visited vet after vet helping clear Ranger of parasitic infections, thyroid issues and other ailments, the sisters said. Christina Maxouris, CNN, "This German Shepherd who will look like a puppy forever is the best thing on Instagram," 26 Nov. 2019 Infectious disease researchers at UAB have secured nearly $1.5 million in funding from the U.S. Centers for Disease Control to look for parasitic hookworm infections in Alabama’s Black Belt region. Dennis Pillion |, al, "UAB researchers launch $1.5 million hookworm study in Alabama’s Black Belt," 21 Nov. 2019 The medication is used to treat parasitic infections typically found in infants, pregnant women, and HIV patients. Kevin Mccoy, USA TODAY, "Supreme Court rejects 'Pharma Bro' Martin Shkreli's final appeal," 19 Nov. 2019 The average sea lamprey kills up to 40 pounds of fish during its adult, parasitic stage. John Myers, Twin Cities, "Parasitic sea lamprey numbers remain too high in Lake Superior," 13 Nov. 2019 The doctors treated the man with a blood transfusion and the anti-parasitic drug triclabendazole, which is used specifically to treat liver flukes. Beth Mole, Ars Technica, "Watch this beautifully disgusting liver fluke parasite explore man’s innards," 8 Nov. 2019 These typically parasitic animals latch onto the inside of the jelly for a free ride, protection and a portion of its food. Kelso Harper, Scientific American, "Undying Cells, Speedy Ants and a Deep-Sea Ghost: Science GIFs to Start Your Halloween Week," 28 Oct. 2019 Anna Ward for The Forbes Lab, The University of Iowa To deposit its eggs, the parasitic oak gall wasp pierces a leaf or stem with its ovipositor, a long tubelike organ that would be a stinger if this wasp were the kind that stings. Joanna Klein, New York Times, "There Are Parasitic Wasps, and Then There’s the Crypt-Keeper," 27 Sep. 2019 That’s not value-added to society; that’s a zero-sum game that is almost parasitic. New York Times, "What’s the Coolest Thing Bill Gates Is Doing?," 11 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'parasitic.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of parasitic

1630, in the meaning defined at sense 1

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Time Traveler for parasitic

Time Traveler

The first known use of parasitic was in 1630

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Statistics for parasitic

Last Updated

29 Nov 2019

Cite this Entry

“Parasitic.” The Dictionary, Merriam-Webster Inc., Accessed 7 December 2019.

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More Definitions for parasitic


How to pronounce parasitic (audio)

English Language Learners Definition of parasitic

of an animal or plant : living in or on another animal or plant and getting food or protection from it
: caused by a parasite
disapproving : getting food, money, etc., from other people without doing anything to earn it or deserve it


par·​a·​sit·​ic | \ ˌper-ə-ˈsi-tik \

Kids Definition of parasitic

: relating to or having the habit of a parasite : caused by parasites a parasitic worm parasitic diseases


par·​a·​sit·​ic | \ ˌpar-ə-ˈsit-ik How to pronounce parasitic (audio) \
variants: also parasitical \ -​i-​kəl How to pronounce parasitical (audio) \

Medical Definition of parasitic

 (Entry 1 of 2)

1 : relating to or having the habit of a parasite : living on another organism
2 : caused by or resulting from the effects of parasites

Other Words from parasitic

parasitically \ -​i-​k(ə-​)lē How to pronounce parasitically (audio) \ adverb



Medical Definition of parasitic (Entry 2 of 2)

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More from Merriam-Webster on parasitic

Spanish Central: Translation of parasitic

Nglish: Translation of parasitic for Spanish Speakers

Britannica English: Translation of parasitic for Arabic Speakers

Comments on parasitic

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