In honour of a police operation, raising one's glass (8)
I believe the answer is:
toasting
'raising one's glass' is the definition.
(I've seen this before)
'in honour of a police operation' is the wordplay.
'in honour of' becomes 'to' (I can't justify this - if you can you should give a lot more credence to this answer).
'police operation' becomes 'sting' (I've seen this in another clue).
'to'+'a'+'sting'='TOASTING'
Can you help me to learn more?
(Other definitions for toasting that I've seen before include "Raising glasses" , "Raising one's glass" , "Drinking a health to" , "Browning" .)