A transsexual is someone who believes they were born in the wrong gender and who wishes to change genders or has actually undergone surgery in order to change genders. (noun)
An example of a transsexual is a man who believes he should have been born a woman.
An example of a transsexual is a man who undergoes surgery to become a woman.
See transsexual in Webster's New World College Dictionary
☆
noun
a person who is predisposed to identify with the opposite sex, sometimes so strongly as to undergo surgery and hormone injections to effect a change of sex