Father got a turn from the contents of the box (6)
I believe the answer is:
curate
'contents of the box' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'father got a turn' is the wordplay.
'father' becomes 'cure' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'got' indicates putting letters inside.
'turn' becomes 't' (abbreviation in Oxford Dictionary of Abbreviations).
'a'+'t'='at'
'cure' placed around 'at' is 'CURATE'.
'from the' is the link.
Can you help me to learn more?
(Other definitions for curate that I've seen before include "Member of the clergy" , "Parish priest's assistant" , "He whose egg is good in parts" , "Acuter (anag.)" , "Clergyman assisting a vicar" .)