Medical Dictionary

menarche

noun men·ar·che \ˈmen-ˌär-kē\

Medical Definition of MENARCHE

:  the beginning of the menstrual function; especially :  the first menstrual period of an individual
men·ar·che·al \ˌmen-ˈär-kē-əl\ or men·ar·chal \men-ˈär-kəl\ also men·ar·chi·al \men-ˈär-kē-əl\ adjective

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