Operator
Operator , noun
[Latin]
1.
One who, or that which, operates or produces an effect.
2.
(Surgery) One who performs some act upon the human body by means of the hand, or with instruments.
3.
A dealer in stocks or any commodity for speculative purposes; a speculator. [Brokers' Cant]
4.
(Mathematics) The symbol that expresses the operation to be performed; -- called also facient.
5.
A person who operates a telephone switchboard.
6.
A person who schemes and maneuvers adroitly or deviously to achieve his/her purposes.