Fool to act smug on air (9)
I believe the answer is:
ignoramus
'fool' is the definition.
(I've seen this in another clue)
'act smug on air' is the wordplay.
'smug on air' anagrams to 'IGNORAMUS'.
Though, I am unsure how the anagram is indicated.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for ignoramus that I've seen before include "Fool" , "At the present time" , "One who knows nothing" , "One could be blissful it's said" , "unwitting person" .)