Go topless in European river for picture (5)
I believe the answer is:
photo
'for picture' is the definition.
(a photograph)
'go topless in european river' is the wordplay.
'go topless' becomes 'hot' (I can't justify this - if you can you should believe this answer much more).
'in' indicates putting letters inside.
'european river' becomes 'po' (river of Italy).
'hot' going within 'po' is 'PHOTO'.
Can you help me to learn more?
(Other definitions for photo that I've seen before include "Snap - shot" , "Still" , "Snap (abbrev.)" , "In brief, a snapshot" , "Pic (abbr)" .)