Wiktionary
vb. (context intransitive figuratively English) topple, collapse
Usage examples of "tumble down".
He is scared that I will throw his stick out into the storm, that it will tumble down the mountainside, and he will lose it.
He fought the urge to throw Eltsac off the trail and let him tumble down into Trench Park.
Mayhap if I merely let it guide me, mayhap I won't tumble down within.
Rocks tumble down from the high rock columns all around them and crash into the waters.
We pop into existence in darkness, tumble down a hill, and roll apart.
There was a moment's flight, and then came the punishing tumble down the rocky slope.
The wood and coal began to tumble down as they climbed the ladder propped against it, and they laid her gently down and hurried away.
I tumble down before I get to the old place, at a point where I was all right before, and stop to think.