Was low in discontent (7)
I believe the answer is:
repined
'was low' is the definition.
I can't judge whether this definition defines the answer.
'discontent' is the wordplay.
I cannot quite understand how this works, but
'discontent' could be 'repine' (I have seen 'Express discontent ' mean 'repine' so perhaps 'discontent' could also mean 'repine') and 'repine' is present in the answer.
A single letter 'd' remains which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
'in' acts as a link.
Can you help me to learn more?
(Other definitions for repined that I've seen before include "Fretted; was discontented" , "Languished" , "Regretted" , "Grudged" , "Expressed discontent" .)