(Greek > Latin: a suffix; one who believes in; one who is engaged in; someone who does something)

An expert in radiobiology or the branch of science concerned with effects of light and of ultraviolet and ionizing radiations on living tissues or organisms.
rapist (s) (noun), rapists (pl)
Someone who forces another person to have sexual intercourse: The serial rapist was caught by the police and confined to jail until a court appearance.

The newspapers reported on a gang of rapists who were terrorizing the city.

rapturist (s) (noun), rapturists (pl)
A person who believes he or she will be transported into the spiritual realm, sometimes applied to the second coming of Jesus Christ, when true believers are expected to rise up to join Him in heaven: In an unprecedented action, the rapturists sold all of their worldly belongings and gathered at the river with joyful expressions on their faces in anticipation of meeting their Lord.
razrapophilist (s) (noun), razrapophilists (pl)
A person who is very fond of razorblade packets: When Kitty's father shaved, he used a razor with a sharp-edged piece of steel fixed in it. Kitty thought the little containers for them were really cute, and, as a razrapophilist, wanted to save them, so her father gave them to her, of course without the razorblades in them!
1. Tending to or expressing an awareness of things as they really are: "The doctor tried to give him a realistic appraisal of his chances of surviving the operation."
2. Of or relating to the representation of objects, actions, or social conditions as they actually are.
3. A reference to seeking what is achievable or possible, based on known facts.
4. Simulating real things or imaginary things in a way that seems real; such as, computer games with realistic graphics.
3. Trying to be reasonable; such as, having a realistic price for something that is not priced or valued too low or high.
4. In the arts and literature, representing life as it really is, rather than an idealized version of it.
receptionist (s) (noun), receptionists (pl)
repudiationist (s) (noun), repudiationists (pl)
Someone who refuses to accept any action or situation which he or she rejects: George is often a repudiationist of President Trump's pro, then negative, then pro inconsistent policies.
1. Any advocate of doctrines, theories, or practices that depart from the established authority or doctrine.
2. Someone who attempts to reevaluate and to restate the past based on newly acquired standards.
3. A member of a movement who re-examines historical information based on current knowledge.