Closed-class words belong to a list of morphemes that can be considered complete and it is normally rare to find new words added to this list by the very nature of their functions as function words. The types of words which are listed as closed-class are:
... males.
The median income for a household in the village is $48,125, and the median income for a family is $49,375. Males have a median income of $41,719 versus $28,750 ...