1850, "frenzied passion," from Latin oestrus "frenzy, gadfly," from Greek oistros "gadfly; breeze; sting; anything which makes one mad, mad impulse," perhaps from a PIE *eis- (1), forming words denoting passion (see ire). First attested 1890 with specific meaning "rut in animals, sexual heat." Earliest use in English (1690s) was for "a gadfly." Related: Estrous (1900).
权威例句
1. The next estrus was delayed.
下一次发情推迟了.
2. A cow's estrus cycle averages 21 days.
母牛的发情周期平均为21天.
3. Anestrus ( absence of estrus ) is not a disease but a sign of a variety of conditions.
乏情不是一种疾病,而是一种多方面的体态迹象.
4. In cows and many other animals, the female is in estrus just before ovulation.
母牛和许多其他的雌性动物都正好是在排卵前发情.
5. During estrus, the female is fertile and will accept a male.