Transphobia (or less commonly cissexism, transprejudice, trans-misogyny, referring to transphobia directed toward trans women and trans-misandry, referring to transphobia directed toward trans men) is a range of negative attitudes and feelings towards transsexualism and transsexual or transgender people, based on the expression of their internal gender identity (see Phobia – terms indicating prejudice or class discrimination). Whether intentional or not, transphobia can have severe consequences for the target of the negative attitude. Many trans people also experience homophobia from people who associate their gender identity with homosexuality. Attacking someone on the basis of a perception of their gender identity rather the perception of their sexual orientation is known as "trans bashing", as opposed to "gay bashing".
Read more about Transphobia: Etymology and Use, Origins, Examples, Transprejudice, Transphobia in The Gay, Lesbian, and Bisexual Communities