Hoping to include fastener (3)
I believe the answer is:
pin
'fastener' is the definition.
(pin is a kind of fastener)
'hoping to include' is the wordplay.
'to include' indicates a hidden word.
'PIN' is hidden in the letters of 'hoping'.
(Other definitions for pin that I've seen before include "Flagged stick placed in golf hole" , "Initially, confidential number for use of bank card" , "Badge" , "Needle" , "Fastener; brooch" .)