Some paper in streamers (4)
I believe the answer is:
ream
'some paper' is the definition.
(I've seen this before)
'in streamers' is the wordplay.
'in' indicates the answer is hidden within the clue.
'REAM' is hidden within 'streamers'.
(Other definitions for ream that I've seen before include "Widen out (bore)" , "Many bits of paper" , "Twenty quires of paper" , "480 sheets of paper" , "stock of paper" .)