Meaning of OPERATOR in English

n.1 a person operating a machine etc., esp. making connections of lines in a telephone exchange.

2 a person operating or engaging in business.

3 colloq. a person acting in a specified way (a smooth operator).

4 Math. a symbol or function denoting an operation (e.g. x, +).

Etymology: LL f. L operari (as OPERATE)

Oxford English vocab.      Оксфордский английский словарь.