The Stultum manuever is something you say when you're trying to sound smart. Can be used in any context as a substitute for almost any adjective. Can be used when you have no real explanation for a series of events. For example, lightning striking that tree was an example of the Stultum Manuever.
Translates to Latin to mean "Foolish." This is because when you use it, everyone will be stunned at your knowledge and will be rendered fools.
Me: I can't believe I got that girls number! All thanks to my signature move.
Friend: What's your signature move.
Me: I just use the Stultum Manuever