Standard item holding papers together (6)
I believe the answer is:
staple
'standard' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for staple that I've seen before include "Paper pin for plates" , "Paper pin - basic" , "Secure" , "Important; paper fastener" , "Principle - fixer" .)