Biphobia is the fear of or bad treatment of bisexual people. Biphobia is different from homophobia. Members of the LGBTQIA+ community can be biphobic as well as cisgender heterosexual people can be biphobic. Bisexual people may feel like their sexual orientation is less real than that of a monosexual (person who is attracted to one gender). This is internalized biphobia.
A biphobic stereotype is that bisexual people have more sex than monosexual people. Some people associate bisexuality with polyamory. Bisexual women may be called nymphomaniacs. Another belief is that bisexuality does not exist. Some people think that bisexual people are heterosexual or homosexual people who are confused.