aposematism

noun

ap·​o·​sem·​a·​tism ˌa-pə-ˈse-mə-ˌti-zəm How to pronounce aposematism (audio)
zoology
: the use of a signal and especially a visual signal of conspicuous markings or bright colors by an animal to warn predators that it is toxic or distasteful : warning coloration
Ladybugs are a good example of aposematism, when the bright colors of red, orange, yellow and black serve as a defense mechanism that warns potential predators of past poisonous or unappetizing results.—Carol Coogan, Times Union (Albany, New York), 16 June 2008

Word History

Etymology

aposemat(ic) + -ism

First Known Use

1979, in the meaning defined above

Time Traveler
The first known use of aposematism was in 1979

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Rhymes for aposematism

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Cite this Entry

“Aposematism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aposematism. Accessed 7 Jul. 2026.

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