Booyakasha was taken from Da Ali G Show.. It's his own way of making the word Booya his own.
Check at dis dictionary website fin. it's fit wicked. i think i am gonna erbal remedy my load all ova my monita now coz i dig it. BOOYAHKASHA!
An extended form of booyah. Adds emphasis to your proclomation of joy.
I had sex with your girl last night. Booyahkasha!