Obliteration (7)
I believe the answer is:
erasure
'obliteration' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for erasure that I've seen before include "Deletion by an act of expunging" , "group from the 80s" , "clearing of tape" , "Wiping out - English pop duo" , "Rubbing out - English synthpop duo" .)