A crazy or outspoken person on the bus (or train or other public transportation). A person who acts out their own private dramas on the bus, talks to the voices in their head, or otherwise puts on a show for other passengers (see also, Bus Drama)
Some busnut started yelling at a tourist on the subway for bumping into him.
When semen is released from the penis
Yo Blood i bus nuts on that chicks top lip
Instead of saying, you cant cum, you cant bus nut
Arrrrr no, face it, you cant bus nut
noun: People who like buses, typically taking many photos of buses to later put onto a forum and share with other bus nuts. It is their obsession.
Brad is such a bus nut, he takes his camera everywhere in case he will see one!