Norms are expectations set by people in a society that express that societies values, beliefs, and traditions. These norms are what the people who live in a society (typically) adhere to and are guided by. It’s also important to note that not every society or ethnic group has the same set norms.
While this idea is shifting in our society, because norms can change throughout time, some consider homosexuality to be breaking the norm of “conventional” heterosexuality or the male and female relationship.
In Butler’s writing about John/Joan she brings up how abnormal John felt with all the intense gender expectations to be a “normal” girl. All the while John didn’t want to play with dolls and he felt “masculine” which is not the “norm” for a woman. In our society we have a lot of gender norms that dictate how woman and men are supposed to act or look. As an example, there is the norm that women should have long hair and in turn that men should have short hair. Also that only men should play baseball and girls should play softball.
While different people can agree or disagree with set norms in the societies they live in, there is a lot of pressure to conform to norms and when someone fails to do so they could be considered deviant or abnormal.