Men"stru*al (?), a. [L.
menstrualis: cf. F. menstruel. See Menstruous.]
1. Recurring once a month; monthly; gone through
in a month; as, the menstrual revolution of the moon;
pertaining to monthly changes; as, the menstrual equation of
the sun's place.
2. Of or pertaining to the menses; as,
menstrual discharges; the menstrual period.
3. Of or pertaining to a menstruum.
Bacon.