The definition of a fecs is a person who specializes in the study of fecal matter. This type of specialist is often referred to as a fecal matter expert or a fecal matter specialist. Fecs are typically employed in the medical field to help diagnose and treat diseases related to the digestive system. They may also be used to detect the presence of parasites or other organisms in the digestive system. Fecs use a variety of techniques to analyze fecal samples, including microscopy, chromatography, and other laboratory tests. Additionally, fecs can provide valuable information about the overall health of the digestive system by examining the presence of certain bacteria, viruses, and other organisms. Ultimately, fecs are essential in helping to diagnose and treat diseases related to the digestive system.