opˈerand noun

Something on which an operation is performed, eg a quantity in mathematics or, in computing, the values on which program instructions operate

opˈerant adjective

1. Operative
2. Active
3. Effective
4. Denoting behaviour that is spontaneous rather than responding to a stimulus (psychology)

An operator

opˈerāting adjective

operāˈtion noun (also (informal, esp military or surgery) op)

1. The act or process of operating
2. Something that is done or carried out
3. Agency
4. Influence
5. A method of working
6. An action or series of movements
7. A surgical procedure

operāˈtional adjective

1. Relating to operations
2. Ready for action

operāˈtionalism or operāˈtionism noun (philosophy)

The theory that defines scientific concepts by means of the operations used to prove or determine them

operāˈtionalist or operāˈtionist noun and adjective

operāˈtionally adverb

opˈerative adjective

1. Having the power of operating or acting
2. Exerting force
3. Producing effects
4. Efficacious

1. A worker, esp one with special skills
2. A labourer

opˈeratively adverb

opˈerativeness noun

opˈerātor noun

1. A person or thing that operates
2. Someone responsible for the operation of a machine, instrument, or apparatus
3. Someone employed to connect calls, etc, at a telephone exchange
4. Someone who deals in stocks
5. The owner of a store, business, mine, etc (US)
6. A symbol, signifying an operation to be performed (mathematics)
7. A crooked or calculating person, a shark (informal, esp US)
8. A sequence of DNA to which a repressor or an activator (a protein which increases the production of a gene product) can bind (biology)

operant conditioning noun (psychology)

A learning procedure in which the subject's response to a stimulus is reinforced if the response is desired

operating system noun (computing)

A collection of programs that controls the activities of a computer system (also called systems software)

operating table noun

The narrow table on which the patient lies during a surgical operation

operating theatre or operating room noun

A room in a hospital, etc equipped for the performing of surgical operations

operational amplifier noun

A very stable high-gain amplifier used in electronic circuits

operational research or operations research noun

1. Research to discover how a weapon, tactic or strategy can be altered to give better results
2. Similar research to promote maximum efficiency in industrial spheres

operative words plural noun

1. The words in a deed legally effecting the transaction (eg devise and bequeath in a will)
2. (loosely; often in sing) the most significant word or words