1) An affirmative or indifferent acknowledgement exclamation to mostly any statement; sometimes used facetiously.
When preceded by the words "oh man" phat city should always be sarcastic exclamation.
While orginally derived from the term "phat", "phat city" does not carry the suburban wannabe connotations and is not an acronym for Pretty Hot And Tempting. The addition of the word city makes "phat" communal, applicable to more situations, and less obnoxious.
"We gonna roll to Ro-Pa tonight to see some Loyola peeps"
"Yo G$, we ran out of booze."