It belongs to us in due course (3)
I believe the answer is:
our
'it belongs to us' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'in due course' is the wordplay.
'in' indicates a hidden word.
'OUR' is hidden within 'due course'.
Can you help me to learn more?
(Other definitions for our that I've seen before include "''Now is the winter of ... discontent'' (Richard III)" , "Belonging to us" , "Relating to us" , "Possessed by us" , "Yours and mine" .)