What is the material left after food has been digested called?

The material left after food has been digested is commonly referred to as "waste." This encompasses the byproducts of digestion that the body does not absorb or utilize and must subsequently be excreted. After food is broken down in the digestive system, the nutrients are absorbed into the body, while the leftover materials, which include undigested food, bacteria, and other components, are expelled as waste.

Chyme is a completely different substance; it is the semi-liquid mass that forms in the stomach after food is mixed with digestive juices before being passed into the small intestine. Fiber refers specifically to certain plant materials that are not fully digestible and plays a crucial role in digestive health, but it is a component of the waste rather than the term used to describe the entirety of what is left after digestion. Residue can refer to what is left after a process, but in the context of digestion, "waste" is the most accurate term to describe the excretory products.