A latch or catch is a type of mechanical fastener that joins two objects or surfaces while allowing for their regular separation. A latch typically engages another piece of hardware on the other mounting surface.

What does it mean when someone is latching?

If someone latches onto a person or an idea or latches on, they become very interested in the person or idea, often finding them so useful that they do not want to leave them. [informal]

Does latch mean lock?

A latch is a lock on a door which locks automatically when you shut the door, so that you need a key in order to open it from the outside.