Sheep accept love, but wander (4)
I believe the answer is:
roam
'wander' is the definition.
('roam' can be a synonym of 'wander')
'sheep accept love' is the wordplay.
'sheep' becomes 'ram' (ram is a kind of sheep).
'accept' means one lot of letters goes inside another.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'ram' going around 'o' is 'ROAM'.
'but' is the link.
(Other definitions for roam that I've seen before include "'Wander, ramble (4)'" , "Move about aimlessly" , "Peregrinate" , "Ramble without purpose" , "Stray" .)