The act of ejaculating in your partners asshole and utilizing the jizz as a lubricant to fornicate anally while the one recieving the booy is in the water face down and has water-wings on so he or she can stay afloat. To add to the authenticity of the act it is helpful if the women points at the man and yells BOOOOOOOYYYYY.
"Bam!", "in your face", and "hell yeah", all at the same time. A term that self-congratulates, describes excitement, lets others know the magnificence of the celebration as well as the superiority of the user, and is used as an exclamation of those ideas.
Say "booya!" when you play a trick on someone or beat them at a game, or prove your superiority to others.