Definition of oestrus in English:

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Pronunciation: /ˈiːstrəs/
(US estrus)


[mass noun]
A recurring period of sexual receptivity and fertility in many female mammals; heat: a mare in oestrus
More example sentences
  • ‘When the female is in estrus, breeding bulls that are 35 to 55 years old and in their prime can be many miles away,’ Garstang said.
  • Judging from mating rate, I found that female topi antelopes in estrus preferred lek males to resource defenders.
  • A beef cow has a 21-day estrous cycle, the period from one estrus, or heat, to the next.



Pronunciation: /ˈiːstrəs/
Example sentences
  • In contrast, it is proposed that estrous females on lek easily escape harassment by switching between the small territories.
  • Social rank then determines access to estrous ewes during the rut.
  • To assess whether shadowing was linked to estrus, we required an estimate of the likely estrous period for females.


Late 17th century: from Greek oistros 'gadfly or frenzy'.

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