A word which has no actual meaning but is just shouted when one wishes to get attention.
Very common to see this word used in fast chatrooms, in general discussion on subways, or just when you feel like you're being ignored.
Basically a word that no attention whore can live without.
Woman: "I saw a star last night, it was big."
Man: "You're wrong lady, it was cloudy last night."
Little girl: "ABOOGALA!"
Woman: "Oh my God, I'm sorry for ignoring you sweetie!"