Repair minute object (4)
I believe the answer is:
mend
'repair' is the definition.
(I know that repair can be written as mend)
'minute object' is the wordplay.
'minute' becomes 'm' (abbreviation).
'object' becomes 'end' (I've seen this in other clues).
'm'+'end'='MEND'
(Other definitions for mend that I've seen before include "Return to health; repair" , "'Restore, fix (4)'" , "Heal" , "Fix, repair" , "Make improvements" .)