Detritus
Detritus. It's what the decomposers feed on/eat.
Decomposing plant and animal matter, along with other dead material, are collectively called "detritus." Detritus serves as an important source of nutrients for decomposers in an ecosystem.
Plant and animal remains, along with other dead matter, are collectively called organic material or organic matter. This material decomposes and breaks down over time into simpler compounds, enriching the soil with nutrients for new plant growth.
When plants and animals (any living matter) decay, their remains are in the soil, in the material called humus.
Detritivores
A scavenger eats the remains of dead animals.
Scavengers and bottom feeders survive on dead animal and plant matter, or detritus. Accordingly they are also known as detrivores, playing a critical aspect to the food cycle and circle of life.
Another word is "consumer." All animals are, by definition, heterotrophs; they cannot synthesize their own food and so must eat other organisms for the organic compounds necessary for survival. However most fungi, and many bacteria and protozoa are also heterotrophic.
The dark decaying matter in soil is called humus. Humus is a rich organic material that forms as plant and animal remains decompose, contributing to soil fertility and structure.
IIt is called organic matter.
Decayed matter that becomes part of the soil is called organic matter. This includes leaves, plant material, animal remains, and other organic substances that break down and contribute nutrients to the soil. Organic matter is important for soil fertility and structure.
The nuclei deep within the cerebral hemisphere white matter are collectively called basal ganglia. These structures are involved in many motor functions and play a role in various cognitive functions as well.
The streams of charged particles flowing out into Space from the Sun are collectively the Solar Wind.