Bro (subculture) – Wikipedia

Bro is a subculture of young men who spend time partying with others like themselves. Although the popular image of bro lifestyle is associated with sports apparel and fraternities, it lacks a consistent definition.Most aspects vary regionally such as in California where it overlaps with surf culture. Oxford Dictionaries have noted that bros frequently self-identify with neologisms containing …

: https://en.wikipedia.org/wiki/Bro_(subculture)