Love unaltered watering hole (5)
I believe the answer is:
oasis
'watering hole' is the definition.
(I've seen this before)
'love unaltered' is the wordplay.
'love' becomes 'o' (In tennis, 'love' means 'zero').
'unaltered' becomes 'asis' (I've seen this in other clues).
'o'+'asis'='OASIS'
(Other definitions for oasis that I've seen before include "Florist's foam" , "Green spot; rock group" , "quiet spot" , "source of water" , "British band" .)