亡 (wáng): To flee, escape, lose, or perish. In this context, it implies both “fleeing” from justice and having a disregard for one's own life (considering it already “lost”).
命 (mìng): Life, fate, or destiny.
之 (zhī): A grammatical particle that connects the preceding words to the following noun, similar to “of” or an apostrophe-'s' in English. It links the state of “fleeing/disregarding life” to the person.
徒 (tú): A person, follower, or disciple. Here, it simply means “a person” or “an individual,” often with a slightly negative or lowly connotation (as in “convict”).
When combined, `亡命之徒` literally translates to “a person of a fleeing/lost life.” This paints a powerful image of an individual who is running from something and has already written off their own existence, making them unpredictable and perilous.