any of several plants of the Eurasian genus Leonurus, esp L. cardiaca, having divided leaves and clusters of small purple or pink flowers: family Lamiaceae (labiates)
Word origin
C14: so named because it was thought to be beneficial in uterine disorders
motherwort in American English
(ˈmʌðərˌwɜrt)
noun
any of a genus (Leonurus) of weedy plants of the mint family; esp., an Old World perennial (L. cardiaca) with pink or purplish flowers and a spiny, toothed calyx
Word origin
ME moderwort (see mother1 & wort2): from the notion that it was helpful in curing diseases of the womb