The sound a dinosaur makes, as documented by greeting cards worldwide. "Braaap" is thought to be the dinosaur equivalent of the human's celebratory "Huzzah!" and/or the dinosaur's way of saying "Happy Birthday". Palentologists have been studying the verbal possibilites of dinosaurs and reached only inconclusive and unsubstantiated results.
"On Tony the Dinosaur's 24th birthday, the other members of the tribe greeted him with an uproarious 'BRAAAP!'"