n. One who operates in any way, or on or against anything.n. One who performs a surgical operation.n. One who exercises power, labor, skill, or influence in the accomplishment of some end; one who manipulates something, or is engaged in carrying on a series of acts or transactions by which some intended result is to be reached: as, a telegraph-operator; a Wall-street operator; an operator in wheat.n. In mathematics, a letter or other character signifying an operation to be performed, and itself subject to algebraical operation: as, a vector operator.n. where x, y, z are the rectangular coördinates of the variable point in space where the operand is found, and i, j, k are unit vectors respectively parallel to x, y, z.n. One who conducts a business, as mining; a capitalist who carries on a business: opposed to operative.