n.1. a. One who operates a machine or device: the operator of a forklift.
b. The owner or manager of a business.
c. A military person who executes a special operation.
d. Informal A person who is adept at accomplishing goals through shrewd or unscrupulous maneuvers.
2. Mathematics A function, especially one from a set to itself, such as differentiation of a differentiable function or rotation of a vector.
3. A logical operator.
4. Genetics A chromosomal segment of DNA that regulates the activity of the structural genes of an operon by interacting with a specific repressor.