A young man who has not assumed (or has been denied) the traditional roles of a man might also be called a boy.
It may feel uncomfortable to a young male upon being referred to as a "man" before he believes he has assumed these roles, such as having a career, a partner, a household of his own, fatherhood, etc., though the addition of a jocular modifier such as "young man" or "little man" might lessen the dissonance.
In some Middle Eastern cultures, characteristics affirming boyhood include physiological features associated with prepubescence, such as pubelessness and the inability to ejaculate.An adult male human is a man, but when age is not a crucial factor, both terms can be interchangeable, e.g., 'boys and their toys' applies equally to adults and young boys, just as 'Are you mice or men? The age boundary is not clear cut, rather dependent on the context or even on individual circumstances.There is often a number of traditional differences in attire between boys and adult men, which may even give rise to a metaphoric term such as broekvent in Dutch (i.e., a boy who has not yet "graduated" from shorts to trousers) and in what is socially accepted as appropriate behaviour, e.g., boys may be publicly seen naked in cultures where men are not.The following subsections treat some specific contexts where the term boy is frequently used, as such or in compound terms, often 'emancipated' from the age notion as such.Shark Boy for a wrestler with matching costume), may also connote to the informal or naughty image of boyhood.
In such terms as 'city boy' or 'home boy', the age notion is at most anachronistic, as they indicate any male who grew up (or by extension lived a long time) in a certain environment.Expressions such as "boys will be boys" (i.e., a male always retains a tendency for boyish games or mischief) allude to stereotypically ascribed characteristics of boys and men; in the term tomboy, a woman's (according to the counterpart-gender stereotype) uncharacteristically bold nature is even described solely by comparing her to a boy.The use of boy (like kid) in (fantasy or descriptive) nicknames, also for adult men (e.g.leerjongen 'learning boy' in Dutch) or lowest rank implying specific on the job training if promotion is to be obtained, as in kitchen boy.Similarly schoolboy only applies to minors; the modern near-synonym pupil originally designated a minor in Roman law as being under a specific adult's authority, as in loco parentis.In US urban slang, particularly in African American and Latino slang, the term boy is used with a possessive as meaning friend (my boy, his boys), presumably as a reduction of homeboy, originally a male from the same area.