Notice small young lady wearing ring (9)
I believe the answer is:
dismissal
'notice' is the definition.
(I know that dismissal is a type of notice)
'small young lady wearing ring' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'young lady' becomes 'miss' (term of address for a young woman).
'wearing' is an insertion indicator.
'ring' becomes 'dial' (I've seen this before).
's'+'miss'='smiss'
'smiss' going within 'dial' is 'DISMISSAL'.
(Other definitions for dismissal that I've seen before include "Process of being sent away" , "Termination of employment" , "Release - marching orders!" , "removal from office" , "getting cards?" .)