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Webster 1913 Edition

Noun.

(Bot.)

(a)

A labiate herb (

Leonurus Cardiaca

), of a bitter taste, used popularly in medicine; lion’s tail.

(b)

The mugwort. See

motherwort ‎(plural motherworts)

Any of several perennial plants, of the genus Leonurus, used in traditional medicine to help with childbirth or treat uterine disorders. [from 13th c.]
- 1653, Nicholas Culpeper, The English Physician Enlarged, Folio Society 2007, p. 195:
  Besides, it makes women joyful and mothers of children and settles their wombs as they should be; therefore we call it Motherwort.

plant