-or; -our (primarily British)

(Latin: a suffix; state of, result of; he who, that which)

A suffix that forms nouns. British spelling is usually -our.
craniotractor
A type of cranioclast (instrument for crushing the head of a fetus, to facilitate delivery in difficult eases) which can also be used to apply traction to the fetus.
creator
1. A person who grows, makes, or invents things.
2. A reference to the Judeo-Christian God.
creditor (s) (noun), creditors (l)
A person or an organization that is owed money by someone else or a company: Todd was making monthly payments to a financial company who was the creditor of the money that he borrowed.
cremator
One who cremates or practices the cremation of corpses.
cryosistor
A cryogenic semiconductor device that, after ionization, can act as a three-terminal switch, a pulse amplifier, an oscillator, or a unipolar transistor.
decapitator (s) (noun), decapitators (pl)
decorator (s) (noun), decortors (pl)
1. A person who specializes in interior ornamentations or beautifications: Elizabeth studied to become a decorator of hotels; as well as, apartment buildings.
2. People who specialize in designing the interiors of buildings and their furnishings: The company hired decorators to paint and to wallpaper houses and other buildings in the community.
deflector
dictator (s) (noun), dictators (pl)
1. A person exercising absolute authority of any kind or in any sphere; one who authoritatively prescribes a course of action or says what is to be done: When a country is run by a dictator, he or she has total and complete command over the people and can often be very cruel.
2. A person who tells a writer what to put into print: When Johann Sebastian Bach was very old and became blind, he acted as a dictator when he told his son-in-law to write down the notes for his music.
director (s) (noun), directors (pl)
1. An individual who has been chosen to be in charge of an organization, a department, or of an activity: Mr. Black was appointed to be the funeral director in the funeral home in the small town.
2. One of the members of a committee who watches over the proceedings or transactions of a business or of something of public interest: There is evidently some friction and misunderstanding between the shareholders and the board of directors in the business that is located in the town where Joan lives.
3. Someone who is in charge of a camera crew, staff for a movie, the actors for a television program, a drama, or for comparable productions: Not only was Jackie the director of the play, but she also wrote it herself!

Janet, who had a lot of experience in stage productions, was the assistant director for the musical that was going to be put on by and for the students at the local high school.

disfavor
dishonor
dissertator
Someone who talks or holds forth formally about a topic.
dissimulator (s) (noun), dissimulators (pl)
A person who professes beliefs and opinions that he, or she, does not have in order to conceal real feelings or motives; a hypocrite, a phony, or a pretender.
doctor (s) (noun), doctors (pl)
1. Someone who is qualified and licensed to give people medical treatment: Alicia was a doctor or physician who was trained in the healing arts and licensed to practice her skills in one of those fields.
2. A title used before the names of health professionals; such as, dentists, veterinarians, and osteopaths: Dr. is used as a title and form of address for a person holding the degree of doctor.
3. A title given to someone who has been awarded a doctorate: To achieve the degree of doctor is considered to be the highest level of an academic award by a university or college.

In the earlier history of the Roman Catholic Church, a doctor was a very eminent and influential theologian.