I. ˈmən(t)thlē, -li adverb
Etymology: month + -ly (adverb suffix)
: once a month : by the month
the annuity is payable semiannually, quarterly, or monthly — J.B.Maclean
II. adjective
Etymology: month + -ly (adjective suffix)
1. : of or relating to a month: as
a. : payable every month
monthly allowances to parents for the maintenance … of the child — Current Biography
b. : reckoned by the month
an average monthly wage
c. : based on a month
a monthly rate
monthly statistics
2. : having a duration of one month : completed in a month
the monthly revolution of the moon
3. : occurring, appearing, or being made, done, or acted upon every month or once a month
produces a monthly television show
a monthly magazine
III. noun
( -es )
1. : a periodical that is published regularly once a month
2. monthlies plural : a menstrual period