The word hemorrhoid came from two Greek words "haimo", for blood, and "rhein", for flow. In anatomy, hemorrhoids refer to cushions of tissue filled with a network of blood vessels located in the lower rectum and anal canal. The veins in this area of the body are quite flexible and stretchable to support the bowel during defecation - the process by which humans eliminate solid or semisolid waste material from the digestive tract.
This is the only vein capable of stretching that much and that big when pressurized with blood. Since the blood vessels are akin to veins, they can also end up as a varicose just like those common with the veins on the legs. These swollen hemorrhoids are simply referred to as hemorrhoids in USA, haemorrhoids in UK, hemroids or emerods. The most popular reference slang to them is "piles". The veins are located at varying locations near the opening of the rectum and along the anal canal. This means, swollen veins can occur at different locations, too. Because of this variety of hemorrhoids, medical experts have classified them into two types: external and
internal. External hemorrhoids is a condition that occurs due to increased pressure on the hemorrhoid veins outside the anus. These external hemorrhoids are prone to thrombosis, a condition wherein the swollen
vein is ruptured and blood clots form. If the engorged vein is inside the rectum, within the last two inches, it is referred to as an internal hemorrhoid. An internal hemorrhoid that hangs outside, enough for the swollen vein to be visible is classified as a prolapsed hemorrhoid. These prolapsed hemorrhoids may protrude during bowel movement and retract afterwards either naturally or manually. External hemorrhoids may bleed due to hard stool or wiping too hard that may cause scratching.
