To choke or cough in a loud obvious way to draw attention to something unbelievable, outrageous or gross.
I totally kacked at that dude Kim brought to the party.
When your dog chokes and it literally sounds like the word "Kack".
Dog: "KACK! "
Owner: " Honey I found my other sock."
vb intr. - messed up, broken, not functioning according to design
(vb. trans. - kack = break)
The sysadmin finally resigned himself to the fact that -- despite his best efforts -- the Linux server was kacked.
I walked up to this girl and I said "Let's Kack!" and she was like "Aiight take me home baby"