Notes spies getting large beauty treatment (6)
I believe the answer is:
facial
'beauty treatment' is the definition.
(I've seen this in another clue)
'notes spies getting large' is the wordplay.
'notes' becomes 'fa' ().
'spies' becomes 'CIA' (Central Intelligence Agency).
'getting' says to put letters next to each other.
'large' becomes 'L' (eg in clothes sizes).
'fa'+'cia'+'l'='FACIAL'
(Other definitions for facial that I've seen before include "Beauty treatment for front of head" , "Cosmetic treatment" , "Beauty treatment, maybe mudpack" , "Beauty treatment for the visage" , "Type of beauty treatment" .)