American Gothic writer covering short song is revelation (10)
I believe the answer is:
apocalypse
'revelation' is the definition.
('Apocalypse' can be a synonym of 'revelation')
'american gothic writer covering short song' is the wordplay.
'american gothic writer' becomes 'apoe' (I can't justify this - if you can you should give a lot more credence to this answer).
'covering' is an insertion indicator.
'short' means to remove the last letter.
'song' becomes 'calypso' (I've seen this before).
'calypso' with its final letter taken off is 'calyps'.
'apoe' going around 'calyps' is 'APOCALYPSE'.
'is' is the link.
(Other definitions for apocalypse that I've seen before include "This last book" , "World's end" , "the last item" , "prophetic disclosure" , "terrible event" .)