Time before inevitable cancellation (7)
I believe the answer is:
erasure
'cancellation' is the definition.
(thesaurus)
'time before inevitable' is the wordplay.
'time' becomes 'era' (an era is a period of time).
'before' says to put letters next to each other.
'inevitable' becomes 'sure' (similar in meaning).
'era'+'sure'='ERASURE'
(Other definitions for erasure that I've seen before include "Rubbing out - English synthpop duo" , "Band with Andy Bell and Vince Clarke, or wipe-out" , "Obliteration - rare use (anag)" , "Obliteration of data" , "Effect of surface damage" .)