Imply, no fire (7)
I believe the answer is:
inferno
'fire' is the definition.
(I've seen this before)
'imply no' is the wordplay.
'imply' becomes 'infer' (I've seen this before).
'infer'+'no'='INFERNO'
(Other definitions for inferno that I've seen before include "Large dangerous fire" , "(Fiery) Hell" , "Huge conflagration" , "Hellish poem" , "Terrible fire" .)