What is hasp and staple?

Answer 1

The "staple" is that rounded tab with a hole in it that you find on lockers, cabinets, safes, etc, and the "hasp" is the slotted thing (hinged latch, door, drawer, etc) that goes over it before you throw a padlock through the staple hole to secure the sliotted thing.

You'll often find that dictionaries use this meaning of "staple" when you look under "hasp", but not under "staple" even if there are five defitions for it. This is a mechanical engineering term for a very common latch we take for granted but never know what to call it.