obnoxionado
A person who thinks they're the greatest because they know one thing and can’t stop talking about it, even if it’s nonsense.
My uncle says he’s the best at everything, even though he can’t spell his own name.
She posted, 'I know more about space than you ever will.' I know about space. I just don’t want to argue with her.
He started a debate about whether the moon is made of cheese. It wasn’t.