It’s a celebration word. A world that describes complete happiness. Like when you do something they say can’t be done, or when you skydive, or when you have your first kid. Extreme high light of your life!
This word first appeared several decades ago, in the brilliant comedy film Monty Python's Quest For The Holy Grail, from the Monty Python team. It is said by the leader of the...knights-who-all-too-recently-said-ni when he tells Arthur they're no lnoger the knights who say ni.
I froget the exact word, but he says "we now the knights who say <something>woopetang<some more nonsesne, trailing off into just a nosie>"