Salver carrying underwear -- mockery (8)
I believe the answer is:
travesty
'mockery' is the definition.
(I know that mockery can be written as travesty)
'salver carrying underwear' is the wordplay.
'salver' becomes 'tray' (I've seen this before).
'carrying' is an insertion indicator.
'underwear' becomes 'vest'.
'tray' enclosing 'vest' is 'TRAVESTY'.
(Other definitions for travesty that I've seen before include "Burlesque, parody" , "Terrible distortion of something." , "Absurd representation" , "'Farce, parody (8)'" , "Farcical version" .)