1. To have different social classes, religions, races, etc. living together in a society but all of which continue to have their own traditions and interests: Jack and Jill were a couple who pluralized their racial backgrounds since she was of African descent with dark skin and he was a White with light-colored skin.
2. To use a grammatical morpheme to indicate a noun to be more than one: In her essay for school, Grace made sure that she pluralized the substantives in the correct manner by adding an "s", like boys, girls, parents, etc.