Transsexual Asian male lying on a bed.
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Definition: Tranphobia is an irrational fear of, and/or hostility towards, people who are transgender or who otherwise transgress traditional gender norms. Because lesbians and gay men often transgress gender norms, it is often associated with homophobia.

The most direct victims of transphobia are people who are transsexual--those who are labeled one sex at birth but transition into another sex later.

The cause of transphobia is still a subject of research and debate, but it likely reflects the fragile nature of gender identity. Men's and women's lives, genes, and bodies are not terribly different; the fact that someone can convincingly identify as a member of the opposite sex calls the very concept of gender into question. People who are quietly struggling with their own gender identity, and people for whom gender identity is especially important, might be frightened--even angry--when confronted with the fragility of gender.