detritus

noun

1. (countable, usually)Pieces of rock broken off by ice, glacier, or erosion.
2. (uncountable, usually)Organic waste material from decomposing dead plants or animals.

   “Woody detritus is an important component of forested ecosystems. It can reduce erosion and affects soil development, stores nutrients and water, provides a major source of energy and nutrients, and serves as a seedbed for plants and as a major habitat for decomposers and hetereotrophs.”

3. (broadly, uncountable, usually)Any debris or fragments of disintegrated material.

   “But of course: no clutter. No newspapers, no renegade scraps of domestic detritus, no rubber bands, paper clips, coupons, pens or pencils, notebooks, magazines. No knives. Where were the knives?”

   “The cutting head removes any chips out of the railhead and restores the required surface shape. The trains also clear up their own detritus as they travel. Neither milling chips nor grinding dust remain on the track.”

4. (uncountable, usually)Rock consisting of accumulated debris from decayed rocks, like sand, that often is joined by cement.