Circular, ring-shaped flap (3)
I believe the answer is:
ado
'flap' is the definition.
(I've seen this before)
'circular ring-shaped' is the wordplay.
I cannot quite see how this works, but
'circular' could be 'o' (I've seen this in other clues) and 'o' is located in the answer.
The remaining letters 'ad' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for ado that I've seen before include "Pother" , "Busy activity, trouble" , "Flap" , "Fuss, difficulty" , "stir" .)