Fastener mending pants with glue! (6,3)
I believe the answer is:
staple gun
'glue' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'fastener mending pants' is the wordplay.
'fastener' becomes 'staple' (staple is a kind of fastener).
'mending pants' becomes 'gun' (I can't justify this - if you can you should believe this answer much more).
'staple'+'gun'='STAPLE GUN'
'with' acts as a link.
Can you help me to learn more?
(Other definitions for staple gun that I've seen before include "Tool for inserting fasteners" , "One that fires those fixing" .)