Noun

(en noun)

someone who moderates

* Walton

Angling was a moderator of passions.

# an arbitrator or mediator

# the chair or president of a meeting etc.

the person who presides over a synod of a Presbyterian Church

(physics) a substance (often water or graphite) used to decrease the speed of fast neutrons in a nuclear reactor and hence increase likelihood of fission

a device used to deaden some of the noise from a firearm, although not to the same extent as a suppressor or silencer.

(UK) An examiner at Oxford and Cambridge universities.

* '>citation

(Ireland) At the University of Dublin, either the first (senior) or second (junior) in rank in an examination for the degree of Bachelor of Arts.

A mechanical arrangement for regulating motion in a machine, or producing equality of effect.

Noun

(en noun)

One who operates.

*

, title=(The Celebrity), chapter=1 , passage=The stories did not seem to me to touch life. […] They left me with the impression of a well-delivered stereopticon lecture, with characters about as life-like as the shadows on the screen, and whisking on and off, at the mercy of the operator .}}

A telecommunications facilitator whose job is to establish temporary network connections.

(mathematics) A function or other mapping that carries variables defined on a domain into another variable or set of variables in a defined range.

Chinese whispers.

(informal) A person who is adept at making deals or getting results, especially one who uses questionable methods.

A member of a military Special Operations unit.

(computing) The administrator of a channel or network on IRC.

(linguistics) A kind of expression that enters into an a-bar movement dependency and is said to bind a variable.

In the sentence "What did Bill say he wants to buy?", "what" is an operator , binding a phonetically empty variable.