Enmity encountered in Tehran courthouse (7)
I believe the answer is:
rancour
'enmity' is the definition.
(rancour is a kind of enmity)
'in tehran courthouse' is the wordplay.
'in' says the answer is hidden in the clue.
'RANCOUR' is hidden in the letters of 'tehran courthouse'.
'encountered' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for rancour that I've seen before include "'Bitterness, resentment (7)'" , "Malicious hostility" , "Deep-seated enmity" , "Spiteful hostility" , "Feeling of bitterness or dislike" .)