: a period immediately preceding estrus characterized by preparatory physiological changes
Word History
Etymology
New Latin
First Known Use
1906, in the meaning defined above
Medical Definition
proestrus
noun
pro·es·trus -ˈes-trəs
variants or proestrum
-ˈes-trəm
or chiefly British pro-oestrus or pro-oestrum
-ˈēs-
: a preparatory period immediately preceding estrus and characterized by growth of graafian follicles, increased estrogenic activity, and alteration of uterine and vaginal mucosa