ˈmenztr(əw)əl, -n(t)str- adjective
Etymology: Middle English menstruall, from Latin menstrualis, from menstrua menses (from neuter plural of menstruus of a month, monthly, of menstruation, from mensis month) + -alis -al — more at moon
1. : of or relating to menstruation
2.
[Latin menstrualis, from menstruus + -alis -al]
archaic
a. : occurring once a month : monthly
b. : lasting for a month
a menstrual flower