[1] : The Collaborative International Dictionary of English v.0.48

menstruation \men`strua"tion\, n.
   the discharge of the menses; also, the state or the period of
   menstruating.
   1913 webster

[2] : WordNet (r) 2.0

menstruation
     n : the monthly discharge of blood from the uterus of
         nonpregnant women from puberty to menopause; "the women
         were sickly and subject to excessive menstruation"; "a
         woman does not take the gout unless her menses be
         stopped"--hippocrates; "the semen begins to appear in
         males and to be emitted at the same time of life that the
         catamenia begin to flow in females"--aristotle syn: menses,
          menstruum, catamenia, period, flow
see also:
menses menstruum catamenia period flow 

Menstruation >> M Words
Menstruation, definition of term: Menstruation
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