Finish in Queer Street, becoming most sore (9)
I believe the answer is:
tenderest
'most sore' is the definition.
(I've seen this before)
'finish in queer street' is the wordplay.
'finish' becomes 'end' (synonyms).
'in' indicates putting letters inside.
'queer' indicates anagramming the letters.
'street' is an anagram of 'terest'.
'end' put within 'terest' is 'TENDEREST'.
'becoming' acts as a link.
(Other definitions for tenderest that I've seen before include "most sore" , "least macho?" , "Most sympathetic" , "Most compassionate" , "Most gentle" .)