Adjective. Someone whose gender identity differs from the one that was assigned to them at birth. Many transgender people identify as either male or female, while others may see transgender as an umbrella term and identify as gender nonconforming or queer. How transgender people choose to express their gender is individualistic, as is their transition.
(NOTE: Avoid using transgender as a noun, as in “a transgender,” or with an extraneous -ed on the end, as in “transgendered.”)