"Boom De Ah Dah" is something you say, sing, yell etc., when you are very happy, and wish to state to your surroundings that you love the world.
It is known from Discovery Channel's advertisements, in which various people from Discovery (including Myth Busters, Bear Grylls, Mike Rowe and Richard Machowicz) sing a song called "The World is Just Awesome" together with a wide variety of people non-famous people, or people not known from Discovery (Astronauts, monks, Stephen Hawking, etc.)
I love the whole world, and it's such a brilliant place! Boom De Ah Dah!

Man, it's been a great day, and the sun is shining brightly! Boom De Ah Dah!
by SimonSan May 18, 2010
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