An expression of great joy. Used by dickheads after receiving good news. Usually followed by the surrounding people telling the user to STFU.
Maths teacher: "So the answer is..."
James: "Kee kee kachey!"
Everyone else: "STFU James!"

"Kee kee kachey!" shouted Tom, as he jizzed all over Amber's face.
by muffaroo March 11, 2011
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