Baseboy
A cocky kid who plays baseball and thinks he's the shit.
Baseboy: I hit 3 home runs last game
You: stop being such a fuckin' baseboy
You: stop being such a fuckin' baseboy
Baseboi
Very confident sexy lad usually works in a manual/technical job i.e. landscaper, roofer, plaster, usually has at least one full sleeve of tattoos, always wears a cap, and not unusual to see them wearing shorts in winter, has a skin fade hair cut.
Look at Jason, got his scaffolding up in less than half an hour. What a baseboi