Estrus is defined as the period of sexual heat in a female.(noun)
An example of estrus is the period of time when a female animal is looking for a sexual mate.
See estrus in Webster's New World College Dictionary
Origin: ModL < L oestrus, gadfly, horsefly, frenzy < Gr oistros, gadfly, sting, frenzy < IE base *eis-, to move violently > ON eisa, to rush on, L ira, ire, Lith aistra, violent passion
See estrus in American Heritage Dictionary 4
Origin: New Latin
Origin: , from Latin oestrus, frenzy, gadfly
Origin: , from Greek oistros; see eis- in Indo-European roots.
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