Uncertain place to go, when retreating into background (10)
I believe the answer is:
ambivalent
'uncertain' is the definition.
(synonyms)
'place to go when retreating into background' is the wordplay.
'place to go' becomes 'lav' (short for lavatory, somewhere to 'go').
'when retreating' is a reversal indicator.
'into' is an insertion indicator.
'background' becomes 'ambient' (I can't explain this - if you can you should believe this answer much more).
'lav' in reverse letter order is 'val'.
'val' inserted inside 'ambient' is 'AMBIVALENT'.
Can you help me to learn more?
(Other definitions for ambivalent that I've seen before include "Having opposing attitudes" , "Having mixed feelings (towards something)" , "with conflict in mind" , "Showing conflicted attitude" , "With conflicting emotions" .)