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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.


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

"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

parasitism Scientific  
/ părə-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


Other Word Forms

  • nonparasitism noun

Etymology

Origin of parasitism

First recorded in 1605–15; parasite + -ism

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The Kobe University discovery blurs the line between mutualism and parasitism and sheds light on the evolution of complex plant-insect interactions.

From Science Daily • Feb. 19, 2024

“When you add this significant stressor of parasitism to the equation, I think it's a perfect storm,” she says.

From National Geographic • Feb. 15, 2024

There’s a biological phenomenon known as parasitism, a relationship in which a parasite benefits while its host is harmed.

From Seattle Times • Aug. 4, 2023

Among ants, social parasitism has evolved about 91 times, he points out.

From Science Magazine • Mar. 5, 2023

Maria did not realize until later in her life that these “false changes”—moth cocoons that produced flies or wasps instead of moths—were caused by insect parasitism.

From "The Girl Who Drew Butterflies: How Maria Merian's Art Changed Science" by Joyce Sidman