-ism, -ismus

(Greek, ismos; Latin, ismus: a suffix: belief in, practice of, condition of, process, characteristic behavior or manner, abnormal state, distinctive feature or trait)

megadactylism
Relating to an excessive size of one or more fingers and/or toes.
megadontism
meiomerism
A condition of lacking some parts.
melanism
mentalism
1. The doctrine that objects of knowledge have no existence except in the mind of the perceiver.
2. The doctrine that human conduct reflects the operation of a nonmaterial principle.
3. Any psychological theory that accepts as a proper subject of study the mental basis for human behavior.
4. Parapsychological activities; such as, telepathy and mind reading.
5. The belief that some mental phenomena cannot be explained by physical laws.
mesmerism
1. Originally, a system of therapeutics propounded by Mesmer.
2. A precursor of hypnotism, believed by Mesmer to involve animal magnetism.
3. By extension, the power to fascinate in a way that is almost hypnotic.

This term is named for the physician Franz (originally Friedrich) Anton Mesmer (1734-1815), who advocated his theory of animal magnetism or mesmerism. Mesmer stroked his patients first with magnets and later with his hands, believing he possessed animal magnetism. Mesmer's system of therapeutics was a forerunner of modern hypnotism.

An example from literature: "At first, when as a young man he began to dip into the secrets of mesmerism, his mind seemed to be wandering in a strange land where all was chaos and darkness, save that here and there some great unexplainable and disconnected fact loomed out in front of him." Arthur Conan Doyle, The Captain of the Polestar and other Tales, 1894, p. 84.

mesognathism
Having the jaws slightly projecting; between prognathous (jaws projecting beyond the upper part of the face) and orthognathous (front of the head, or the skull, nearly perpendicular, not retreating backwards above the jaws).
mesomerism
The existence of organic chemical structures that cannot be accurately represented by a single structural formula, the actual formula lying in the middle between several possible representations that differ only in the position of electrons.
mesomorphism
1. A reference to one of the three classic somatotypes, or body types.

Typically speaking mesomorphism refers to people who have strength and an athletic build. They can develop and build [muscle] mass without much difficulty and can usually eat without too much fear of gaining weight.

2. Having physical form, structure, or size which is average, normal, or intermediate between extremes.
metabolism
metachronism
1. An error in chronology consisting in placing an event later than its real date.
2. In biology, the co-ordination of the movement of parts; especially, cilia, into a progressive wave.
metamerism
A situation in which there are many parts joined together.
metamorphism
1. Mineralogic and structural changes in solid rocks caused by physical conditions which are different from those under which the rocks originally were formed.
2. A process of change in the physical structure, texture, or composition of rocks caused by agents of heat, deforming pressure, shearing stress, hot, chemically active fluids, or a combination of these, acting while the rock that is being changed remains essentially in the solid state.

Theoretically, rocks are formed when their constituents are in equilibrium with ambient physical conditions. If the conditions are changed by movements in the earth's crust or by igneous activity, metamorphism occurs to re-establish equilibrium and it changes the physical character of the rock mass.

meteorism
Distention of the abdomen or intestines due to the presence of gas; tympanites.
microcephalism