if ain't the belle of the ball !!! what DOES* that mean !!!
Nothing, unless "if" is a typo for "it" or possibly "if it". The 'belle of the ball' is the most attractive woman at a social occasion, and "ain't'" in that context suggests a note of sarcasm - "if it ain't the belle of the ball" might be said sneeringly when someone arrives expecting to get all the attention.
*An easy mistake to make if you've learnt the informal expression 'what's it mean?'