Définition : A landform that extends above the surrounding terrain in a limited area. A mountain is generally steeper than a hill, but there is no universally accepted standard definition for the height of a mountain or a hill although a mountain usually has an identifiable summit and a local relief of more than 300m.
Définition : A wavelike sequence of muscular contraction and relaxation that passes along a tubelike structure, such as a vertebrate intestine, or the body of an earthworm
Définition : movement of an organism from one location to another using an inchworm like motion. This motion consists of extending the front part of the body and pulling the rear along the surface to meet the front.
