Make things right in relation to the frock (7)
I believe the answer is:
redress
'make things right' is the definition.
'redress' can be an answer for 'make' (thesaurus). I am not certain of the 'things right' bit.
'relation to the frock' is the wordplay.
'relation' becomes 're' (re is a kind of relation).
'to the frock' becomes 'dress' (synonyms).
're'+'dress'='REDRESS'
'in' is the link.
Can you help me to learn more?
(Other definitions for redress that I've seen before include "Correct" , "Prepare again - satisfaction" , "set straight again" , "relief" , "Pay" .)