To love more (3)
I believe the answer is:
too
'more' is the definition.
(thesaurus)
'to love' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'to'+'o'='TOO'
(Other definitions for too that I've seen before include "To a greater than desirable extent" , "Likewise" , "As well; in addition" , "Additionally" , "As well, also" .)