A1
a piece of metal cut into a particular shape that is used for opening or closing the lock of a door, starting a car engine, etc.
Dictionary examples:
My dog ate the car key! (0.0)
I use a banana as my car key! (0.0)
The key is bigger than the door! (0.0)
I forgot my key. Can I use yours? (0.0)
The dog ate my homework and keys! (0.0)
I found my keys in the refrigerator! (0.0)
car/door/house keys (32.1)