FASTEN [I, T] › 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 › 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.