Get nurses behind surgery high on gas (6)
I believe the answer is:
bubbly
'high on gas' is the definition.
Both the answer and definition are adjectives. Perhaps you can see an association between them that I don't see?
'get nurses behind surgery' is the wordplay.
'get' becomes 'buy' (buying is a kind of getting).
'nurses' indicates putting letters inside (nurse can mean to hold onto or harbour).
'behind surgery' becomes 'bbl' (I can't explain this - if you can you should believe this answer much more).
'buy' enclosing 'bbl' is 'BUBBLY'.
Can you help me to learn more?
(Other definitions for bubbly that I've seen before include "lively" , "Champers" , "Drink" , "Effervescent" , "Informal champagne" .)