They once made a bolt for it (8)
I believe the answer is:
crossbow
'it' is the definition.
The definition suggests a singular noun which matches the answer.
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for crossbow that I've seen before include "historic weapon" , "Old weapon with mechanism for firing arrow" , "Ancient weapon, shot bolts" , "William Tell's weapon" , "One responsible for shooting bolts" .)