Big fire? Deduce otherwise (7)
I believe the answer is:
inferno
'big fire?' is the definition.
(I've seen this before)
'deduce otherwise' is the wordplay.
'deduce' becomes 'infer' (synonyms).
'otherwise' becomes 'no' (I am not sure about this - if you are sure you should believe this answer much more).
'infer'+'no'='INFERNO'
Can you help me to learn more?
(Other definitions for inferno that I've seen before include "Uncontrollable fire" , "hot spot" , "Large uncontrolled fire" , "Dante's scene of horror" , "Big fire" .)