bub
noun [ C ] US old-fashioned informal uk/bʌb/ us/bʌb/
（用于打招呼，有时稍显恼火）老弟
a form of address used to a man, sometimes in a slightly angry way
That may be what you do at home, but listen, bub, you don't do it here! 老弟，你在家可以这么干，但听着，在这儿可不行。