(Internet) A network operator on IRC.

The act of operating or working; operation.

operativeness

Obsolete form of operose.

(algebra, computing) A symbol representing unary operation; an operator taking one operand.

(algebra, computing) A symbol representing binary operation; an operator taking two operands.

(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.

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.

A company that sells package holidays.

A subcontractor who may be a commercial carrier, but most often provides capacity (trucks and drivers, with or without trailers or chassis) to either commercial or private carriers under a contract for services.