: a cold-blooded animal : poikilotherm

Examples of ectotherm 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.
Hammerheads are ectotherms—or cold-blooded creatures—which means their body temperatures are regulated by their environment. Margaret Osborne, Smithsonian Magazine, 12 May 2023 For instance, brumation comes as an advantage for ectotherms’ longevity. Sofia Quaglia, Discover Magazine, 24 Feb. 2023

Word History

First Known Use

1940, in the meaning defined above

Time Traveler
The first known use of ectotherm was in 1940

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Cite this Entry

“Ectotherm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ectotherm. Accessed 24 Mar. 2025.

Kids Definition

ectotherm

noun
: a cold-blooded animal : poikilotherm

Medical Definition

ectotherm

noun
: a cold-blooded animal : poikilotherm
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