Not to be scoffed at, a French expert’s clothing (9)
I believe the answer is:
uneatable
'not to be scoffed' is the definition.
I can't judge whether this defines the answer.
'at a french expert's clothing' is the wordplay.
'a french' becomes 'une' ('a' in French).
'expert' becomes 'able' (I've seen this before).
'clothing' is an insertion indicator (some letters cover up or clothe others).
'une'+'able'='uneable'
'at' going into 'uneable' is 'UNEATABLE'.
Can you help me to learn more?
(Other definitions for uneatable that I've seen before include "not fit for consumption" , "pursued unspeakably?" , "disgusting when dining" , "can't be taken in!" , "Can't be kept down" .)