Awkward moment in case of surgery (6)
I believe the answer is:
sticky
'awkward' is the definition.
(I know that awkward can be written as sticky)
'moment in case of surgery' is the wordplay.
'moment' becomes 'tick' (both can mean a very short amount of time).
'in' means one lot of letters goes inside another.
'case of' means to remove the middle letters (outsides of).
'surgery' with its centre removed is 'sy'.
'tick' inserted within 'sy' is 'STICKY'.
(Other definitions for sticky that I've seen before include "sultry?" , "Glutinous, gooey" , "Adhesive; awkward" , "Twiggy" , "Awkward - viscous" .)