op·er·a·tor / ˈäpəˌrātər/ • n. 1. a person who operates equipment or a machine: a radio operator. ∎  (usu. the operator) a person who works for a telephone company assisting users, or who works at a telephone switchboard.2. a person or company that engages in or runs a business or enterprise: a tour operator.3. inf. a person who acts in a specified, esp. a manipulative, way: her reputation as a cool, clever operator.4. Math. a symbol or function denoting an operation (e.g., ×, +).

operator
1. A person responsible for the immediate supervision of the hardware of a computer system.

2. A function that can be applied to one or more operands so as to yield a result. It is (usually) a symbol representing an operation to be carried out, as opposed to a variable, which represents a data value. See also arithmetic operator, logic operation, relational operator, precedence.

operator A region of DNA at one end of an operon that acts as the binding site for a specific repressor protein, and so controls the functioning of adjacent cistrons.

operator The region of DNA at one end of an operon that acts as the binding site for a specific repressor protein, and so controls the functioning of adjacent cistrons.