Defecation is the process by which organisms eliminate solid, semisolid, or liquid waste material known as feces from the digestive tract via the anus. It is a complex function that requires coordinated involvement from the gastrointestinal system, the nervous system, as well as the musculoskeletal system. Defecation follows digestion and is a necessary process for eliminating undigested portions of food and metabolic waste products from the body. Here are some key points about defecation:

• Defecation may also accompany childbirth and death. Babies defecate a unique substance called meconium prior to eating external foods.
• The frequency of defecation within a 24-hour period varies depending on age and diet, but most people tend to have a bowel movement 1 to 3 times daily.
• The colon is responsible for propelling feces toward the rectum and beginning the urge to defecate. The external anal sphincter and the puborectalis muscle relax to allow the passage of feces out of the rectum. Valsalva maneuver and abdominal muscle contraction are performed to increase intra-abdominal pressure and expel feces more rapidly.
• Regular bowel movements determine the functionality and the health of the alimentary tracts in the human body. Defecation is the most common regular bowel movement which eliminates waste from the human body. The frequency of defecation is hard to identify, which can vary from daily to weekly depending on individual bowel habits, the impact from the environment, and genetics.
• Sometimes, due to the inability to control ones bowel movement or due to excessive fear, defecation (usually accompanied by urination) occurs involuntarily, soiling a persons undergarments. This may cause significant embarrassment to the person if this occurs in the presence of other people or a public place.
• There are a number of medical conditions associated with defecation, such as diarrhea and constipation, some of which can be serious. The feces expelled can carry diseases, most often through the contamination of food.

In summary, defecation is a necessary process for eliminating waste from the body, and it involves the coordinated involvement of several systems in the body.