estrus

noun

es·​trus ˈe-strəs How to pronounce estrus (audio)
: a regularly recurrent state of sexual receptivity during which the female of most mammals will accept the male and is capable of conceiving : heat
Some mares will exhibit estrus for 15 to 20 days. Frederick Harper
also : a single occurrence of this state

Example Sentences

Recent Examples on the Web Plus, deer kept moving in faster than they could be sterilized, which Curtis attributes to new bucks being attracted to the ongoing estrus of the does that didn’t get pregnant. Brooke Jarvis, The New Yorker, 8 Nov. 2021 As a result, the Smithsonian Conservation Biology Institute, headquartered in Front Royal, Virginia, became a leader in giant panda estrus, breeding, pregnancy, pseudopregnancy and cub development. Roger Catlin, Smithsonian Magazine, 7 Dec. 2020 Unlike female lions, which tend to become receptive to mating—also known as coming into heat, or estrus—at the same time, leopards do not. Doug Main, National Geographic, 27 June 2018 The deer was sixty yards away, moving steadily, its head down, probably following the scent of doe in estrus. New York Times, 31 Mar. 2020 Based on traces of sperm found in the days before the birth of the first joey, the researchers found that the wallabies’ estrus, or mating period, began before the pregnancy was over. Veronique Greenwood, New York Times, 2 Mar. 2020 During the peak rut, a lot of estrus does mist the woods, and bucks had lots of choices. Michael Hanback, Outdoor Life, 4 Dec. 2019 The animals are in estrus for only 24 to 72 hours each year. Michael E. Ruane, Washington Post, 27 Aug. 2019 Britain, and Wales in particular, grows lamb at a relatively natural pace, with ewes coming into estrus just once a year, to be mated with rams in the fields, to give birth in the spring, after five months gestation. Washington Post, 17 Aug. 2019 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'estrus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

Etymology

New Latin, from Latin oestrus gadfly, frenzy, from Greek oistros — more at ire

First Known Use

circa 1890, in the meaning defined above

Time Traveler
The first known use of estrus was circa 1890

Dictionary Entries Near estrus

Cite this Entry

“Estrus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/estrus. Accessed 6 Dec. 2022.

Kids Definition

estrus

noun

es·​trus ˈes-trəs How to pronounce estrus (audio)
1
: a periodic state during which the female of most mammals is willing to mate with the male and is capable of becoming pregnant
2
estrous
-trəs
adjective

Medical Definition

estrus

noun

es·​trus ˈes-trəs How to pronounce estrus (audio)
variants or estrum or chiefly British oestrus or oestrum
1
a
: a regularly recurrent state of sexual excitability during which the female of most mammals will accept the male and is capable of conceiving : heat
b
: a single occurrence of this state
2

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