Transgender people experience a mismatch between their gender identity or gender expression and their assigned sex. Transgender is also an umbrella term because, in addition to including trans men and trans women whose binary gender identity is the opposite of their assigned sex (and who are sometimes specifically termed transsexual if they desire medical assistance to transition), it may include genderqueer people (whose identities are not exclusively masculine or feminine, but may, for example, be bigender, pangender, genderfluid, or agender). Other definitions include third-gender people as transgender or conceptualize transgender people as a third gender, and infrequently the term is defined very broadly to include cross-dressers.