noun, noun which may take the genitive case particle 'no', adverb
every month; monthly; month by month
Used as a noun, adjectival modifier with の, or adverbially to describe something happening or being done each month.
The rent is 50,000 yen every month.
月々の支払いを忘れないでください。
Please don't forget the monthly payments.
会費は月々集めています。
We collect the membership fee month by month.
The monthly electricity bill is about five thousand yen.
I'm saving ten thousand yen each month.
The electricity rate varies month by month.