ABC air naughty language (6)
I believe the answer is:
arabic
'language' is the definition.
(Arabic is a language)
'abc air naughty' is the wordplay.
'naughty' indicates anagramming the letters.
'abc'+'air'='abcair'
'abcair' anagrammed gives 'ARABIC'.
(Other definitions for arabic that I've seen before include "Correspond; last word of Othello" , "There's a CIA bar on this language, oddly" , "Official language of Egypt" , "Middle Eastern language" , "foreign language" .)