estrus

[es-truh s] /ˈɛs trəs/
noun, Zoology
1.
Also, estrum
[es-truh m] /ˈɛs trəm/ (Show IPA), oestrus. the period of heat or rut; the period of maximum sexual receptivity of the female.
2.
estrous cycle.
Origin
1885-90; < Latin oestrus oestrus
Related forms
estrual
[es-troo-uh l] /ˈɛs tru əl/ (Show IPA), adjective
Examples from the web for estrus
  • In the wild, nature has tied ovulation closely to the availability of food, and in times of scarcity estrus may not occur.
British Dictionary definitions for estrus

estrus

/ˈɛstrəs; ˈiːstrəs/
noun
1.
the usual US spelling of oestrus
Derived Forms
estrous, adjective

oestrus

/ˈiːstrəs; ˈɛstrəs/
noun
1.
a regularly occurring period of sexual receptivity in most female mammals, except humans, during which ovulation occurs and copulation can take place; heat
Derived Forms
oestrous, oestral, (US) estrous, estral, adjective
Word Origin
C17: from Latin oestrus gadfly, hence frenzy, from Greek oistros
Word Origin and History for estrus
n.

1850, "frenzied passion," from Latin oestrus "frenzy, gadfly," from Greek oistros "gadfly, breeze, sting, mad impulse," perhaps from a PIE *eis, forming words denoting passion (cf. Avestan aešma- "anger," Lithuanian aistra "violent passion," Latin ira "anger"). First attested 1890 with specific meaning "rut in animals, heat." Earliest use (1690s) was for "a gadfly." Related: Estrous (1900).

estrus in Medicine

estrus es·trus or oes·trus (ěs'trəs)
n.
The periodic state of sexual excitement in the female of most mammals, excluding humans, that immediately precedes ovulation and during which the female is most receptive to mating; heat.

estrus in Science
estrus
  (ěs'trəs)   
A regularly recurring period in female mammals other than humans during which the animal is sexually receptive. Estrus occurs around the time of ovulation. Also called heat.