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1.
Yummy-butter is a phrase which can be used to express happiness, glee, and/or pleasure for a certain situation and/or person. The phrase was invented by the Nisenson family and is now a world-wide phenomenon. Yummy-butter: learn it, love it, live it.
Ex. 1:

Hayley: "Holy shit I just hooked up with an Abercrombie and Fitch Model."

Caroline: "Ooo yummy-butter how was it?"

Hayley: "It was fucking amazing!"

Ex. 2

Hayley: "Yo son lets go roll a blunt."

Kinsey: "Yummy-butter."
by Billy Pilgrim IV March 25, 2007