es·​ti·​va·​tion ˌe-stə-ˈvā-shən How to pronounce estivation (audio)
variants or aestivation
zoology : the state or condition of torpidity or dormancy induced by the heat and dryness of summer : the state of one that is estivating
Some animals, including various species of snakes, land snails, and lizards, enter a state of dormancy, or estivation, in the summer when water is scarce.Carrol B. Fleming
… they [land snails of the genus Cerion] spend most of this time in the warm weather equivalent of hibernation (called estivation), hanging upside down from vegetation or affixed to rocks.Stephen Jay Gould
usually aestivation botany : the arrangement or position of the petals or sepals in a flower bud
In practice, aestivation is best observed by making hand sections of mature flower buds …Michael G. Simpson
… flowers on the same plants or the same stem may exhibit either clockwise or counterclockwise spiral estivationsCarlos Herrera
compare vernation

Examples of estivation in a Sentence

Recent Examples on the Web When temperatures reach 113 degrees (45 degrees Celsius) during the dry season, crocodiles will attempt to aestivation — or reduce their body temperature by burying themselves in mud for up to a month without eating, by living off its fat reserves. Camille Fine, USA TODAY, 6 Mar. 2023 Reptiles, amphibians and lungfish also use estivation to ward off long periods of hot weather. Joshua Rapp Learn, Discover Magazine, 30 Aug. 2022 But other creatures use a kind of long-term sleep, called estivation, to get them through extreme heat instead. Joshua Rapp Learn, Discover Magazine, 30 Aug. 2022 No, not death, Rosalie clarified, but stillness, like hibernation or estivation, waiting for . . . Yiyun Li, The New Yorker, 16 Jan. 2023 Warm-weather hibernation, or estivation, is also used by lizards, snails, and turtles. Gregory Mone, Discover Magazine, 19 June 2013

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'estivation.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1783, in the meaning defined at sense 1

Time Traveler
The first known use of estivation was in 1783

Dictionary Entries Near estivation

Cite this Entry

“Estivation.” Dictionary, Merriam-Webster, Accessed 21 Feb. 2024.

Medical Definition


variants or aestivation
: the state of one that estivates

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