On the level with bazaar and plaza (4,3,6)
I believe the answer is:
fair and square
'on the level' is the definition.
(I've seen this before)
'with bazaar and plaza' is the wordplay.
'with' says to put letters next to each other.
'bazaar' becomes 'fair' (synonyms).
'plaza' becomes 'square' (synonyms).
'fair' next to 'and' is 'fairand'.
'fairand'+'square'='FAIR-AND-SQUARE'
(Other definitions for fair and square that I've seen before include "Above board" , "On the level" , "Justly and honestly" , "Rightfully" , "In a proper way" .)