Transmasculine

Transmasculine, often abbreviated to transmasc, refers to people who were assigned female at birth and have a gender identity, gender expression, or both that is predominantly masculine. Transmasculine people may or may not identify as male. It can be a standalone identity term or an umbrella term for certain identities, such as:
 * Transgender men
 * Non-binary people who feel their gender is masculine, whether entirely or partially
 * Genderfluid or multigender people who feel predominantly masculine
 * Demiguys

Resources

 * Transmasculine on Gender Wiki