rubble

The broken remains of an object, usually rock or masonry.

The main East Coast line from Edinburgh to Berwick was blocked at Cockburnspath and Grantshouse by flood water, which washed away part of an embankment, and by the collapse of about 300 tons of rubble on to the track.

The old boulevard now was a sagging ruin, waiting for the wreckers. … You'd have to loathe yourself vividly to be indifferent to such destruction or, worse, rejoice at the crushing of the locus of these middle-class settlements, glad that history had made rubble of them.

A mass or stratum of fragments of rock lying under the alluvium and derived from the neighbouring rock.

The overlying beds are composed of such calcareous rubble and flints, rudely stratified

The whole of the bran of wheat before it is sorted into pollard, bran, etc.

To break down into rubble.