Still a back street whatever people have in mind (8)
I believe the answer is:
thoughts
'mind' is the definition.
(thesaurus)
'still a back street' is the wordplay.
'still' becomes 'though'.
'a back' says the letters should be written backwards.
'street' becomes 'st' (abbreviation).
'st' written backwards gives 'ts'.
'though'+'ts'='THOUGHTS'
'whatever people have in' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for thoughts that I've seen before include "Cogitations" , "Ideas and opinions (8)" , "Ideas, reflections" , "They are in my mind" , "Ideas, musings" .)