n.
A person who ruins all fun, who is uncool and generally
awkward, which makes other
people feel awkward around them.
As geese (the animal) are obnoxious, loud and on the whole
annoying, they are the definitive anti-bro who goes against all fun-having.
Bro1: So I was rocking this
one party the other night, man and bro, it was sweet. That is until
Arthur showed up.
Bro2: Why, what happened, man?
Bro1: He called the cops as soon as we started playing
beer-pong, we all had to run for it.
Bro2: What a goose!