Affable country bumpkin crossing lake (8)
I believe the answer is:
pleasant
'affable' is the definition.
(thesaurus)
'country bumpkin crossing lake' is the wordplay.
'country bumpkin' becomes 'peasant' (informal term for someone from a rural area).
'crossing' is an insertion indicator.
'lake' becomes 'l' (geographical abbreviation).
'peasant' going around 'l' is 'PLEASANT'.
(Other definitions for pleasant that I've seen before include "Nice, satisfying" , "Satisfying, likeable" , "Enjoyable, nice" , "sweet?" , "Charming" .)