parasitic

adjective

par·​a·​sit·​ic ˌper-ə-ˈsi-tik How to pronounce parasitic (audio)
ˌpa-rə-
variants or less commonly parasitical
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.
parasitically 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Lice are parasitic insects that spread through close contact and require prompt treatment with medicated shampoos. Lindsay Curtis, Health, 2 Feb. 2025 NTDs refer to a diverse group of parasitic and bacterial diseases that cause significant morbidity and mortality in more than one billion people around the globe, which disproportionately affect poor and marginalized populations. Joshua P. Cohen, Forbes, 21 Jan. 2025 The center has also led health efforts, including the push to eradicate the tropical parasitic Guinea worm disease. Marty Steinberg, CNBC, 29 Dec. 2024 Tanaka hopes that this kind of research will open up the world of parasitic crickets to the public. Laura Baisas, Popular Science, 16 Jan. 2025 See all Example Sentences for parasitic 

Word History

First Known Use

1630, in the meaning defined at sense 1

Time Traveler
The first known use of parasitic was in 1630

Dictionary Entries Near parasitic

Cite this Entry

“Parasitic.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/parasitic. Accessed 6 Feb. 2025.

Kids Definition

parasitic

adjective
par·​a·​sit·​ic
ˌpar-ə-ˈsit-ik
: of or relating to parasites or their way of life : being a parasite
parasitically
-i-k(ə-)lē
adverb

Medical Definition

parasitic

1 of 2 adjective
par·​a·​sit·​ic ˌpar-ə-ˈsit-ik How to pronounce parasitic (audio)
variants also parasitical
1
: relating to or having the habit of a parasite : living on another organism
2
: caused by or resulting from the effects of parasites
parasitically adverb

parasitic

2 of 2 noun
Last Updated: - Updated example sentences
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