In retrospect, nice street with the odd snoopy exhibitionist (6)
I believe the answer is:
poseur
'exhibitionist' is the definition.
(I know that poseur is a type of exhibitionist)
'in retrospect nice street with the odd snoopy' is the wordplay.
'in retrospect' is a reversal indicator.
'nice street' becomes 'rue' (I've seen this in another clue).
'with' means one lot of letters go next to another.
'the odd' indicates alternate letters.
The alternating letters of 'snoopy' are 'sop'.
'rue'+'sop'='ruesop'
'ruesop' in reverse letter order is 'POSEUR'.
(Other definitions for poseur that I've seen before include "Exhibitionist" , "Affected type" , "One who strikes an attitude to impress" , "Insincere show-off" , "Pretentious person" .)