Arrears of French baronet on vacation (4)
I believe the answer is:
debt
'arrears' is the definition.
(I've seen this before)
'of french baronet on vacation' is the wordplay.
'of french' becomes 'de' ('of' in French).
'on vacation' says to hollow out the word (remove centre letters) (after the inside letters have vacated the word).
'baronet' with its middle removed is 'bt'.
'de'+'bt'='DEBT'
(Other definitions for debt that I've seen before include "Something owed" , "Intertwine" , "What's due" , "Liability, obligation" , "Sum of money that's owed" .)