locksmith
/ˈlɒkˌsmɪθ/Definitions
1. noun
A person who makes, installs, and repairs locks and other fastening devices.
“The locksmith helped me get into my house after I lost my key.”
2. verb
To make or repair locks.
“The locksmithed the old lock to make it more secure.”
3. noun
A device or system that prevents access or operation until a specific combination, key, or code is used.
“The locksmith showed me how to use a combination lock on my bike.”