And what have you that's overdue for return? (2,2)
I believe the answer is:
et al
'and what have you' is the definition.
('et al' means 'and others' in Latin)
'overdue for return?' is the wordplay.
'overdue' becomes 'late' (similar in meaning).
'for return?' says the letters should be written backwards (I've seen 'for return' mean this).
'late' written backwards gives 'ET AL'.
'that's' acts as a link.
(Other definitions for et al that I've seen before include "And others (abbrev.)" , "and everyone else)" , "Latin notation meaning and others" , "'And others, to the old Romans (2,2)'" , "Latin abbreviation meaning 'and others'" .)