Op"er*a`tor (?), n. [L.]
1. One who, or that which, operates or produces
an effect.
2. (Surg.) 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. (Math.) The symbol that expresses
the operation to be performed; -- called also
facient.