B1
the thing that is used to close a door, window, etc., and that needs a key to open it
Dictionary examples:
The new smart lock on my door keeps locking me out accidentally. (0.0)
I forgot the code to my bike lock and had to carry it home. (0.0)
I bought a voice-activated lock, but it only responds to my singing voice. (0.0)
I heard someone turn a key in the lock. (20.7)
safety locks (31.4)
Thieves got in by smashing the lock off the door. (39.0)