Definition

An interjection deployed immediately after a statement to reveal it was false, essentially the verbal equivalent of "just kidding!" Often spelled "psych," it's the classic fake-out move in conversation. It's how you let someone know they've been bamboozled, usually followed by laughter at their expense.

Example Usage

I'm totally going to help you move this weekend—sike! I'll be out of town.

Source: Urban Dictionary (https://www.urbandictionary.com/define.php?term=sike&defid=20695)