That was grama's favorite saying when she was really pissed. She was directly off the boat from Finland, having come to America on her own at age 18. She was a pistol. I never remember seeing grama without a large, well-used butcher knife in her hand. She liked to threaten to slit throats. This was said to the dog barking incessantly next door ("SHUT UP or I'll SLIT YOUR THROAT!") and to the drunken hockey player who foolishly knocked on her door at 3 a.m. demanding a glass of water. Believe me, he tottered off her stoop when she greeted him with the butcher knife and the throat-slitting threat. The threat was always effective as she had at hand the means to turn it into a promise.
She never threatened to slit my throat. But she often said, "You keep up that racket, and down goes your meathouse!". The exact point of her threat would reflect what it was that I was doing that was driving her over the edge, but the dire threat of my meathouse going down was what held me in check.
A couple of years after grama died, I asked my mom what the hell "down goes your meathouse" meant. I think I asked her because of course she used the same phrase. Imagine my chagrin upon discovering that ma had absolutely no idea what it meant. She used the phrase simply because of it's effectiveness.
I've been in a quandry over this since 1988.