parasitism

American  

[par-uh-sahy-tiz-uhm, -si-] / ˈpær ə saɪˌtɪz əm, -sɪ- /

noun

1. Biology. a relation between organisms in which one lives as a parasite on another.

2. a parasitic mode of life or existence.

3. Pathology. a diseased condition due to parasites.

4. (in some totalitarian countries)

   1. unemployment or refusal to work.

   2. employment in work considered nonessential by the state.

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parasitism British  

/ ˈpærəsaɪˌtɪzəm /

noun

1. the relationship between a parasite and its host

2. the state of being infested with parasites

3. the state of being a parasite

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parasitism Scientific  

/ păr′ə-sĭ-tĭz′əm /

1. A relationship between two organisms in which one organism (the parasite) benefits and the other (the host) is harmed. Parasites derive nutrition from their host and may also gain other benefits such as shelter and a habitat in which to grow and reproduce.

2. See more at parasite Compare amensalism commensalism mutualism

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Other Word Forms

• nonparasitism
  noun

Etymology

Origin of parasitism

First recorded in 1605–15; parasite + -ism

Explanation

Parasitism is a relationship between two things in which one of them (the parasite) benefits from or lives off of the other, like fleas on your dog. Parasitism and its root, parasite, come from para-, meaning "beside" or "next to," and sito, meaning "bread or food." There is parasitism in plant life, like the kudzu vine that grows on trees. We also talk about social parasitism, when someone lives at the expense of someone else. Some people think that government programs such as welfare or corporate grants and tax breaks are a form of parasitism.

Example Sentences

Parasitism, of course, is no less noble a lifestyle than any other, but there’s inspiration to be found in a cookie-cutter shark’s particular mode of predation.

From Slate • Nov. 20, 2023

Parasitism is a type of symbiosis, in which animals live in close relationship.

From Salon • Oct. 31, 2023

Parasitism is a symbiotic relationship in which one organism lives inside of or on another organism and harms it.

From Textbooks • Jan. 1, 2018

Parasitism and disease are density-dependent factors because they spread from one host to another more easily when populations are dense.

From Textbooks • Jan. 1, 2018

Parasitism and servile dependence act very much in structural lower life as analogous instances of mental dependence on others act on man.

From Degeneracy Its Causes, Signs and Results by Talbot, Eugene S.