Remorse about runs inside grows (7)
I believe the answer is:
regrets
'remorse' is the definition.
(thesaurus)
'about runs inside grows' is the wordplay.
I cannot quite see how this works, but
'about' could be 're' (regarding) and 're' is located in the answer.
'runs' could be 'r' (cricket abbreviation) and 'r' is located in the answer.
'grows' could be 'gets' ('get' can be a synonym of 'grow') and 'gets' is found within the remaining letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for regrets that I've seen before include "Rues" , "Bemoans" , "Sorrows" .)