What does the term flatus refer to?

The term flatus specifically refers to gas or air that is expelled from the gastrointestinal tract through the anus. This process, known as flatulence, is a normal bodily function and indicates that the digestive system is working as it should. Flatus is composed of various gases, including nitrogen, oxygen, carbon dioxide, hydrogen, and sometimes methane, which can be produced during digestion. This makes the understanding of flatus important in the context of digestive health and changes in gastrointestinal functioning, as variations in the amount or odor of flatus could indicate underlying conditions.

In contrast, the other options refer to different bodily discharge processes and are unrelated to the definition of flatus. Liquid stool specifically pertains to a watery form of bowel movement, solid waste material refers to feces, and excess urine relates to the urinary system and could indicate conditions affecting kidney or bladder function.