Adhesive resin (5)
I believe the answer is:
epoxy
'adhesive resin' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for epoxy that I've seen before include "Synthetic polymer used in adhesives, paints, etc" , "Hard-setting resin" , "Type of resin" , "Synthetic resin used as glue" , "Adhesive; plastic" .)