Trial of a quiet non-amateur (5)
I believe the answer is:
appro
'trial' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'a quiet non-amateur' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'non-amateur' becomes 'pro' (I've seen this in another clue).
'a'+'p'+'pro'='APPRO'
'of' is the link.
Can you help me to learn more?
(Other definitions for appro that I've seen before include "On which goods may go out" , "brief assessment?" , "back" , "awaiting confirmation" , "On which one may examine" .)