Controller and Operator

noun

• Someone who maintains and audits business accounts.
  • synonyms: accountant, comptroller
• A person who directs and restrains.
  • synonyms: restrainer
• A mechanism that controls the operation of a machine.
  • usage: "the speed controller on his turntable was not working properly"; "I turned the controls over to her"
  • synonyms: control

• (n.) An iron block, usually bolted to a ship's deck, for controlling the running out of a chain cable. The links of the cable tend to drop into hollows in the block, and thus hold fast until disengaged.
• (n.) One who or that which, controls or restraines; one who has power or authority to regulate or control; one who governs.
• (n.) An officer appointed to keep a counter register of accounts or to examine, rectify or verify accounts.
• (n.) A kind of multiple switch for gradually admitting the current to or shutting it off from, an electric motor; as, a car controller for an electric railway car.
• (n.) A lever controlling the speed of an engine; -- applied especially to the lever governing a throttle valve, as of a steam or gasoline engine, especially on an automobile.
• (n.) Any electric device for controlling a circuit or system;.
• (n.) An electromagnet, excited by the main current, for throwing a regulator magnet into or out of circuit in an automatic device for constant current regulation.

controller is the chief financial officer of a company, financial institution or other entity. The controller is responsible for supervising the operations of the accounting department and preparing its financial reports. Also spelled comptroller.

noun

• Mathematics) a symbol or function representing a mathematical operation. (
• An agent that operates some apparatus or machine.
  • usage: "the operator of the switchboard"
  • synonyms: manipulator
• Someone who owns or operates a business.
  • usage: "who is the operator of this franchise"
• A shrewd or unscrupulous person who knows how to circumvent difficulties.
  • synonyms: hustler, wheeler dealer
• A speculator who trades aggressively on stock or commodity markets. .

• (n.) One who or that which, operates or produces an effect.
• (n.) One who performs some act upon the human body by means of the hand or with instruments.
• (n.) The symbol that expresses the operation to be performed; -- called also facient.
• (n.) A dealer in stocks or any commodity for speculative purposes; a speculator.