Wandering and strolling by river (8)
I believe the answer is:
rambling
'wandering' is the definition.
(I know that wandering can be written as rambling)
'strolling by river' is the wordplay.
'strolling' becomes 'ambling' (I've seen this before).
'by' is a charade indicator (letters next to each other).
'river' becomes 'r' (abbreviation for river).
'ambling' after 'r' is 'RAMBLING'.
'and' acts as a link.
(Other definitions for rambling that I've seen before include "Roaming" , "Walking about or talking aimlessly" , "Confused; walking for pleasure" , "Taking stroll; not keeping to point" , "Discursive" .)