Bill girl coming out on time (4)
I believe the answer is:
debt
'bill' is the definition.
(thesaurus)
'girl coming out on time' is the wordplay.
'girl coming out' becomes 'deb' (short for debutante).
'on' is a charade indicator (letters next to each other).
'time' becomes 't' (abbreviation).
'deb'+'t'='DEBT'
(Other definitions for debt that I've seen before include "Commitment" , "The state of owing something" , "Financial liability" , "Arrears, liability" , "Liability, obligation" .)