Haphazard money order (6)
I believe the answer is:
random
'haphazard' is the definition.
(similar in meaning)
'money order' is the wordplay.
'money' becomes 'rand' (I've seen this before).
'order' becomes 'om' (Order of Merit).
'rand'+'om'='RANDOM'
(Other definitions for random that I've seen before include "Disorganised" , "Hit-or-miss" , "Chance, unplanned" , "Without order" , "'Haphazard, occurring by chance (6)'" .)