Dye brown paper, cutting top and bottom (4)
I believe the answer is:
anil
'dye' is the definition.
(anil is a kind of dye)
'brown paper cutting top and bottom' is the wordplay.
'brown paper' becomes 'manila'.
'cutting top and bottom' means to look at the middle letters.
The centre of 'manila' is 'ANIL'.
(Other definitions for anil that I've seen before include "Species of blue" , "Dye for nail" , "Shrub providing indigo" , "Source of dye" , "It produces dye" .)