(arithmetic, computing) Any one of the four basic operations in arithmetic: addition, subtraction, multiplication or division; any one of said operations as implemented on a computer.

(algebra) An operation taking two operands.

(law) An application of a legal rule that automatically brings about a legal consequence.

plural of binary operation

A showing of something — such as a variable, term, or object — in terms of the specific process or set of validation tests used to determine its presence and quantity.

(psychology) A technique of behavior modification through positive and negative reinforcement and positive and negative punishment.

(mathematics, physics) A differential operator,denoted ∆ and defined on ℝⁿ as 𝛥=∑ᵢ₌₁ⁿ(∂²)/(∂x_i²), used in the modeling of wave propagation, heat flow and many other applications.

(military) That portion of a theater of war] which an army passes over in attaining its object.

A person who operates a telephone switchboard. / A person who provides assistance in establishing a connection, or who provides information or takes messages via the telephone.

Alternative spelling of cooperative