Another name for fiber is
Fiber is also known as roughage. It is the indigestible part of plant foods that pushes through our digestive system, absorbing water along the way and easing bowel movements. The word fiber (North American) can also be spelled fibre (British).he word fiber is misleading, because many types of dietary fibers are not fibers at all. There are two broad types of fiber, soluble and insoluble. 1  Soluble fiber dissolves in water. 2  It changes as it goes through the digestive tract, where it is fermented by bacteria. 3  As it absorbs water it becomes gelatinous.