Used other than figuratively or idiomatically: see bad, boy. / A man whose rebellious nature makes him dangerous and/or attractive. / (slang) A male criminal.

(chiefly Britain) Someone who has an anonymous support role in an organization, especially a technician or scientist; a boffin.

(UK, US, slang, chiefly in the plural) A policeman. / (UK, air force slang, dated) A member of the air force.

A boy serving as an acolyte in certain forms of Christianity. / A young man adhering to traditional values.

A girlish boy.

(idiomatic) A male exemplar of some trait.

A young man who has become unusually successful at an early age. / A favored youth, held in high esteem by others, and for whom there are high hopes.

(UK) A male day pupil.

(Britain) A boy chosen to lead a school sixth form, whose duties may include representing the school and organising the prefects.

(sports) A person, usually male, responsible for retrieving balls from the area of play, and returning them to the players.