Piece of paper containing these letters (5)
I believe the answer is:
sheet
'piece of paper' is the definition.
(synonyms)
'these letters' is the wordplay.
'letters' is an anagram indicator.
'these' with letters rearranged gives 'SHEET'.
'containing' acts as a link.
(Other definitions for sheet that I've seen before include "Piece of linen; ship's rope" , "Piece of paper or bedlinen" , "Single piece of paper" , "Bedcover" , "Piece of writing paper" .)