Motility

Motility is a biological term which refers to the ability to move spontaneously and actively, consuming energy in the process. Most animals are motile but the term applies to single-celled and simple multicellular organisms, as well as to some mechanisms of fluid flow in multicellular organs, in addition to animal locomotion. Motile marine animals are commonly called free-swimming.

The opposite of motility is sessility.

Motility may also refer to an organism's ability to move food through its digestive tract, i.e., peristaltics (gut motility, intestinal motility, etc.).

Movements
Movements can be:
 * along a chemical gradient (see chemotaxis)
 * along a temperature gradient (see thermotaxis)
 * along a light gradient (see phototaxis)
 * along a magnetic field line (see magnetotaxis)
 * along an electric field (see galvanotaxis)
 * along the direction of the gravitational force (see gravitaxis)
 * along a rigidity gradient (see durotaxis)
 * along a gradient of cell adhesion sites (see haptotaxis)
 * along other cells or biopolymers