-ist

1. A specialist in the area of dentistry concerned with the prevention and correction of abnormally positioned or aligned teeth.
2. A dentist who is concerned with correcting and preventing irregularities of teeth and their poor occlusions.

1. The branch of medicine concerned with the nature and correction of disorders of the bones, joints, ligaments, or muscles.
2. One who cures deformities; an orthopedic surgeon.

Originally from Greek paideia, "child rearing"; applied specifically to childhood bone disorders.

Someone who is a specialist in phonology.

One who practices phrenology.

A physician who specializes in the study, treatment, and prevention of mental disorders.

1. Someone who is trained in methods of psychological analysis, therapy, and research.
2. A specialist in psychology licensed to practice professional psychology (e.g., clinical psychologist), or qualified to teach psychology as a scholarly discipline (academic psychologist), or whose scientific specialty is a subfield of psychology (research psychologist).

A specialist in the science of earthquakes and their effects.

1. Someone who believes in or supports socialism or a socialist party.
2. An advocate of socialism or someone who is a member of a socialist party.

A person who coerces with violence and terror to achieve some objective.