[pearlbubbles]

I've heard it in three contexts: "partying hard," "dressing fratty," and "acting stereotypically (usully negative)." These descriptions are generally used for three very specific fraternities on campus, or specific people within organizations who fall under the above mentioned definitions.

With this in mind, usually the definition is simply implied by context. With specific people, though, the "stereotypical" definition has been used as a positive thing. It's really all contextual; and for the people, at least, the definitions vary depending on whether a friend or a Greek bystander is making the comment.