par·a·sit·ic | \ˌper-ə-ˈsi-tik, ˌpa-rə-\
variants: or less commonly parasitical \ˌper-ə-ˈsi-ti-kəl, 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, 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

The small lab in Berkeley got involved with this complicated worm conundrum through a parasitic disease expert at the National Institutes of Health. Brian Rinker, CNN, "New tech revolutionizes fight against ancient diseases in Africa, Asia," 17 Apr. 2018 An earlier hypothesis is that the thickness and shape of stick insect eggs protects them from parasitic wasps. Joanna Klein, New York Times, "Stick Insects Are Easy Bird Food, and That Might Help Them Reproduce," 5 June 2018 And parasitic sea lice shouldn’t be confused with sand lice, also called sea fleas—another crustacean that lives in wet sand. National Geographic, "What's Giving Some Beachgoers Rashes? Get the Facts.," 28 June 2018 An exploitation some online oligopolies expose music authors to by using legal loopholes and operating a parasitic value creation model. Wolfgang Spahr, Billboard, "German Rights Body GEMA Applauds Europe-Wide Efforts to Curtail 'Parasitic' Value Models of Digital Services," 19 June 2018 Dragonfly larvae feed on mosquito larvae and adult dragonflies feed on adult mosquitoes while Mermithids are a parasitic to mosquitoes. Kaila Contreras, Houston Chronicle, "Harris County breeds carnivorous plants, mosquito assassins to limit mosquito population," 7 July 2018 Wisconsin officials in June confirmed at least 123 cases of the parasitic infection, which some have linked to vegetable trays found in Kwik Trip stores, according to the The Milwaukee Journal Sentinel. Allie Morris, San Antonio Express-News, "Texas health officials investigating rise in Cyclospora infections," 2 July 2018 The original in the print edition erroneously referred to malaria as a viral rather than a parasitic disease. Mariette Dichristina, Scientific American, "Our Planet, Ourselves: How Climate Change Results in Emerging Diseases," 1 May 2018 Schistosomiasis, also known as snail fever and bilharzia, is a parasitic worm infection that slowly destroys the kidneys and liver. The Economist, "How Sierra Leone is beating tropical diseases," 23 June 2018

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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Last Updated

20 Sep 2018

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The first known use of parasitic was in 1630

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More Definitions for parasitic


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 \
variants: also parasitical \-i-kəl \

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 \ 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

What made you want to look up parasitic? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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