1) A term used to depict a time period where a lack of skill, ability, or performance was displayed. It is also used to mock people who "find the cheap way" to play games or perform tasks. This term can be used to many different types of situations.
Examples:
Applied to Work:
Boss: "Damn it Johnson! These papers are NOT in alphabetical order. What is this, Amateur Hour?"
Applied to Video Games:
Player A: "Wow, that kid is using a glitch. I forgot it was amateur hour this time of day."
Applied to Home:
Mom: "Rodney, your room is filthy. I thought I said clean it."
Son: "I did clean it."
Mom: "Did you clean it during amateur hour or something? This is atrocious!"
Applied to School:
Professor: "The class average was a D+ on this exam...seriously class, is it amateur hour when you all come here?"
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.
FRIEND A: "Did you just take a stealthie of me?"
FRIEND B (turning phone around): "no I was just using snapchat's new filter, see?"