Servant's sheet (4)
I believe the answer is:
page
I believe this is a double definition.
'servant's' is the first definition.
(I've seen this before)
'sheet' is the second definition.
(page is a kind of sheet)
(Other definitions for page that I've seen before include "contact" , "Leaf of book etc" , "Summon" , "Leaf; call over PA system" , "Youth acting as a knight's attendant" .)