scree

1. (uncountable) Loose stony debris on a slope.Examples: "To the north the towering scree-strewn slopes of Saddleback begin to draw nearer as we start the abrupt descent towards Keswick."; "Struggling down the slope, There's not much hope. I begin to try to ride the scree But the rocks are tumbling all around me."; "Sprawled prone among the rocks, the team waited for a reply to their request to fire. […] Occasional rounds zinged off the scree, each with a different pitch."uncountable

2. (uncountable, by extension) Similar debris made up of broken building material such as bricks, concrete, etc.Examples: "Acres of the industrial port had been reduced to desolation, half-walls, half-chimneys, crazy sticks of steel that looped up out of concrete scree. The temptation not to clear and rebuild must have been strong."broadlyuncountable

3. (countable) A slope made up of scree at the base of a cliff, mountain, etc.Examples: "The next landmark was an apachita 'cairn', at the top of a steep scree. Each pilgrim carried a stone to the summit, spat on it, and threw it on to the cairn — the purpose being, I was told, to relieve the soul of its sins […]"; "Also, special to Crete, and probably derived from some aspect of its climactic history, is cementation. Many screes are converted, in whole or in part, into concrete-like breccias. Carapaces of cemented scree encrust steep slopes. Cliffs of conglomerate or marl are covered with a layer of re-deposited limestone and look like hard rock. However, the loose contents are apt to trickle out through a breach in the crust, resulting in the jagged and hollow cliffs which are a picturesque feature of Crete"countable