Crease new material (5)
I believe the answer is:
linen
'material' is the definition.
(I know that linen is a type of material)
'crease new' is the wordplay.
'crease' becomes 'line' (synonyms).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'line'+'n'='LINEN'
(Other definitions for linen that I've seen before include "Fabric made from flax" , "bedding" , "bedclothes perhaps" , "Sheets, pillowcases etc" , "Cloth made from flax" .)