Vessel or nutcracker (3)
I believe the answer is:
tun
This might be a double definition.
'vessel' is the first definition.
(tun is a kind of vessel)
'nutcracker' is the second definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'or' is the link.
Can you help me to learn more?
(Other definitions for tun that I've seen before include "Large cask or barrel" , "Barrel holding many gallons" , "Nut found in large cask" , "Quite enough wine" , "Large cask for wine or beer" .)