Air of trio playing - more sound? (1,8)
I believe the answer is:
a fortiori
'more sound?' is the definition.
Both the definition and answer are adverbs. Maybe you can see an association between them that I can't see?
'air of trio playing' is the wordplay.
'playing' indicates an anagram.
'air'+'of'+'trio'='airoftrio'
'airoftrio' with letters rearranged gives 'A FORTIORI'.
Can you help me to learn more?
(Other definitions for a fortiori that I've seen before include "stronger premises" , "even more convincing reasons" , "more convincing reason" , "with greater reason" , "Latin phrase: With even stronger reason than that already accepted" .)