hinge hinge /ˈhɪndʒ/

noun

1. () A joint that holds two parts together so that one can swing relative to the other  ( flexible joint , hinge )
   a joint that holds two parts together so that one can swing relative to the other
    The door hinge squeaked every time it was opened.
   The door hinge squeaked every time it was opened.
   
   
2. A circumstance upon which subsequent events depend  ( hinge )
   a circumstance upon which subsequent events depend
    His absence is the hinge of our plan
   his absence is the hinge of our plan
   

verb

1. Attach with a hinge  ( hinge )
   attach with a hinge