A declaration used to accuse a person, business or an organization of doing something dishonest or using a form of trickery to achieve an end. The declaration is made directly to the party being accused preferably in front of numerous witnesses. The phrase was popularized by the television show South Park.
(1) Suzy orders a pitcher of Yuengling but sees the bartender pull the pitcher from the Bud Light tap. Suzy yells, "I declare shenanagins!!"
(2)The car salesman tells Harold that he needs a $100 check with Harold's offer to show the manager that "he's serious about buying the car." Harold hollers, "I delare shenanagins" and hopefully clears the showroom of customers.