Negative in no time! (3)
I believe the answer is:
not
'negative' is the definition.
(thesaurus)
'no time' is the wordplay.
'time' becomes 't'.
'no'+'t'='NOT'
'in' is the link.
(Other definitions for not that I've seen before include "It negates a word" , "Negation of what follows" , "Ton (anag.)" , "Word of negation" , "Having close-cut hair" .)