Sloppy accountant about to be given smaller amount (8)
I believe the answer is:
careless
'sloppy' is the definition.
(synonyms)
'accountant about to be given smaller amount' is the wordplay.
'accountant' becomes 'CA' (abbreviation for chartered accountant).
'about' becomes 're' (regarding).
'to be given' is a charade indicator (letters next to each other).
'smaller amount' becomes 'less' (I've seen this in another clue).
'ca'+'re'+'less'='CARELESS'
(Other definitions for careless that I've seen before include "Incautious" , "Inattentive to risk" , "Not careful or thorough enough" , "Marked by lack of attention" , "Negligent, unconcerned" .)