operator

Etymology

Borrowed from Latin operatōr, from operor (“work, labour”). Equivalent to operate + -or.

noun

1. One who operates.
2. A telecommunications facilitator whose job is to establish temporary network connections.
3. A member of a military special operations unit.
4. (uncountable) The game of Chinese whispers.
5. (informal) A person who is adept at making deals or getting results, especially one who uses questionable methods.
   Francis Urquhart: I think Lord Billsborough is starting to lose touch a bit. Tim Stamper: Shame. Used to be a hell of an operator in his day. 1990, House of Cards, season 1, episode 1
6. (mathematics) A function or other mapping that carries variables defined on a domain into another variable or set of variables in a defined range.
7. (computing) The administrator of a channel or network on IRC.
8. (computing) A symbol that represents a construct in a programming language and differs from a normal function in its syntax.
9. (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.
10. (transport) A bus driver.
11. (slang) A thief or charlatan.
    Sir Ol. Sirrah! I got many a round Sum by it, when my Father wou'd not give me a Groat—Then, Sir, I was in with all the Top Gameſters, and when there was a fat Squire to be fleec'd; I had my Office among them too, and tho' I ſay it, was one of the neateſt Operators about Town. 1709-01-11, Colley Cibber, “The Rival Fools:[…]”, in Mr. Cibber's Plays, volume II, London: […] B. Lintot[…], published 1721, page 104
    Hank was saying, "Lyssa showed me the screenshots of Nate's accounts, so we know he's helping himself to Nate's money every month. The guy's a real operator." 2016, C. T. Collier, Planted, Scottsdale, A.Z.: Asdee Press, page 301
12. (slang) A major criminal.
    He started bleating to me this morning aboot being stretched on this hippy stalk. A fuckin waste of time. Big operators flooding the city with smack and three-quarters of the cunts we bang up are daft schemies or students with a wee bit of hash or a few pills for their pals. 1998, Irvine Welsh, Filth, New York, N.Y., London: W. W. Norton & Company, page 140
13. (slang, dated) Someone who is successful at pursuing women; a player.
    I give credit to men who are great operators, as we once called them, with the girls. Once I was interviewing one of the most beautiful girls in the world in her suite at the Hotel Plaza. While she was busily denying to me that there was anything serious in her relationship with Warren Beatty, who should be barging into the next room of the suite with a lot of clothes being removed from another suite, but Warren Beatty? 1974, Earl Wilson, Show Business Laid Bare, New York, N.Y.: G. P. Putnam's Sons, page 188
    "Of course you're right, but the Baron is unfortunately a bit of an operator, if you know what I mean. He likes the ladies," said Salvatore with a wicked grin. "So he never gets in until two, sometimes even three in the morning, and that's because he goes dancing at the Mela; he's quite a playboy." 1988 [1977], Luciano De Crescenzo, translated by Avril Bardoni, Thus Spake Bellavista: Naples, Love, and Liberty, New York, N.Y.: Grove Press, page 101
    Anyway, there's gonna be plenty of girls. Plenty of girls for an operator like you. 1996, George P. Pelecanos, The Big Blowdown, New York, N.Y.: St. Martin's Press, page 298