The word ‘month’ is a common noun.
Common nouns refer to general items, people, or concepts, and they do not name a specific entity. In this case, ‘month’ refers to any month in a calendar year, such as January, February, or March, but it does not specify one particular month. Conversely, proper nouns are specific names that denote unique entities, such as the names of people, places, or organizations, like ‘March’ or ‘January’. So, when we say ‘month’, we are referring to a general category rather than a specific one, which classifies it as a common noun.