Official Definition: a person who was assigned female at birth but whose gender identity is male. -Dictionary.com (Link: www.dictionary.com/browse/trans-male).
Transman: a man who was not assigned that gender via sex at birth, and transitioned (socially, medically, and/or legally) from that assignment to their gender identity, signified by the second part of the term ( -man). Also referred to as men (though some/many trans people prefer to keep the prefix "trans-" in their identity label). https://www.itspronouncedmetrosexual.com/2013/01/a-comprehensive-list-of-lgbtq-term-definitions/