Servants in attendance extremely upset, as behind procedure? (5)
I believe the answer is:
enema
'behind procedure?' is the definition.
'servants in attendance extremely upset' is the wordplay.
'servants' becomes 'men' (man is a kind of servant).
'in' indicates putting letters inside.
'extremely' suggests removing the centre.
'upset' says the letters should be written backwards.
'attendance' with its middle removed is 'ae'.
'men' placed within 'ae' is 'amene'.
'amene' reversed gives 'ENEMA'.
'as' is the link.
(Other definitions for enema that I've seen before include "Procedure for vacating the bowels" , "Bowel evacuator" , "Liquid injection given as a laxative" , "treatment by rear entrance" , "process to ensure evacuation" .)