Clare's town losing time in activity in court (5)
I believe the answer is:
ennis
'clare's town' is the definition.
(town in County Clare)
'in activity in court' is the wordplay.
'activity' is an anagram indicator (letters become active).
'in' is an insertion indicator.
'court' becomes 'ens' (I can't justify this - if you can you should give a lot more credence to this answer).
'in' is an anagram of 'ni'.
'ni' inserted into 'ens' is 'ENNIS'.
'losing time' acts as a link.
This may not be correct. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for ennis that I've seen before include "World champ" , "our potential 1/4 Across [GOLD MEDALLIST] in 2012" , "somewhere in Ireland" , "County town of Co Clare, Ireland" , "Poster girl" .)