transgender vs. transsexual

transgender and transsexual: How the Use and Meanings of the Terms Differ

A transgender person has a gender identity that does not correspond to the sex they were assigned at birth. The term transsexual is now considered mostly outdated and often offensive, though some people identify in this way. It was historically used in reference to a person who received treatment or surgery to attain the physical characteristics of a different sex. Some transgender people may undergo such treatment, but transgender identity is not based on physical traits.