Would it be called "overlap door lock"? Instead of being installed inside the door, it is screwed outside of the door.
These are usually called "rim locks" in North America and the UK. Maybe different elsewhere.
I have usually seen these just called "surface-mount locks". I have never seen "rim lock" used in the (Eastern) USA.
One possibility is "rim lock": http://www.houseofantiquehardware.com/rim-lock
In Danmark they are called "kasselås" in danish, which translates to "box lock", probably referring to it being a visible as a box mounted on the outside of the door instead of inside it.
People in the UK often call them "Yale locks", because that is one of the most common brands. Like we usually call Vacuum cleaners "hoovers"