To give a silly example, I could create a new language that only my family knows. In this language, the word "table" means "window." So I have given a new meaning to the word "table".
Conceptual terms may not always have completely clear and non-controversial meanings. So what a person means by the word "masculinity" can vary a lot, depending on his or her culture, age, and political beliefs. We can say: different people give different meanings to the word "masculinity".