Meaning of “lock” - Learner’s Dictionary

lock

verb uk us /lɒk/
FASTEN [ I, T ]

B1 to fasten something with a key, or to be fastened with a key:

Did you lock the door?
If you shut the door it will lock automatically.
→ Opposite unlock
lock sth/sb away/in, etc

B2 to put something or someone in a place or container that is fastened with a key:

She locked herself in her bedroom.
Most of my jewellery is locked away in a safe.
FIXED [ I ]

to become fixed in one position:

I tried to move forward but the wheels had locked.

(Definition of “lock verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)