to suddenly, and without warning, transition from a fully-functional state into a completely non-functional state.
"...and the next thing I knew, he had just conked out, right there in the middle of the room."
A shortened version of the common insult cock munch
Can be applied as a noun in two forms: munch or muncher.
1: You're a stupid munch, get lost.
2: Get away from me you muncher!