Commonly used by Roadmen in Britain, big
man is a term used to tell someone that they are acting bigger than they actually are.
Sometimes you may hear people saying “big
man ting” in that sense it wouldn’t be used to imply someone isn’t actually a big man but instead is implying that the person saying “it’s a big
man ting” is actually a big
man”
Big man means someone who is most likely the leader of the gang.