A plate holder (5)
I believe the answer is:
rivet
This could be a double definition.
'a plate' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'holder' is the second definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
Can you help me to learn more?
(Other definitions for rivet that I've seen before include "make fast" , "Metal bolt that's hammered" , "Completely engross; pin" , "Engross attention" , "Bolt for metal plates" .)