Fade a lot, that is (3)
I believe the answer is:
die
'fade' is the definition.
(thesaurus)
'a lot that is' is the wordplay.
'a lot' becomes 'd' (**).
'that is' becomes 'ie' ('i.e.' can be a synonym of 'that is').
'd'+'ie'='DIE'
(Other definitions for die that I've seen before include "Kick the bucket" , "rolling over - to do this?" , "One spotted" , "Pass from physical life" , "Numbered cube" .)