Boyo, a slang word used to refer to a young man or boy, has a variety of synonyms that might come in handy while writing or conversing. Some of the alternatives to the word boyo are lad, bloke, chap, dude, youngster, youth, juvenile, adolescent, etc. These words vary in applicability in different scenarios and settings, and it's important to choose the right synonym based on the context. For instance, lad might be a better synonym to use while referring to someone in a pub or a working-class setting, while youngster or juvenile could be more appropriate in a formal or academic setting.