Derick remembered. We thought he was saying something like "Boha!" but it was something completely different. But for like a year we went around saying "Boha!" It was funny at the time.
But I'm pretty sure he actually says "porra" which I used to hear ALL THE TIME when I worked at Toys R Us because that old lady I worked with was Portuguese ha ha ha
She said it was just a general profanity used for everything but googling just now the internet says that technically it means "sperm"