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Medical Term:


Pronunciation: an-es′trŭs


The period of sexual quiescence between the estrus cycles of mammals; may be: 1) a prolonged period in monestrous animals (dogs) or seasonally polyestrous animals (sheep), or 2) a prolonged period of failure of estrus in mature nonpregnant, polyestrous animals.

[G. a- priv. + oistros, a gadfly, mad desire (estrus)]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.