duke

Etymology

From Old French duc, through Middle English duk, duke, from Latin dux, ducis. Displaced native Old English heretoga. Was present as duc in late Old English, from the same Latin source. Doublet of dux and doge. The “fist” sense is thought to be Cockney rhyming slang where “Duke(s) of York” = fork. Fork is itself cockney slang for hand, and thus fist.

noun

1. The male ruler of a duchy (female equivalent: duchess).
2. The sovereign of a small state.
3. A high title of nobility; the male holder of a dukedom.
4. A grand duke.
5. Any of various nymphalid butterflies of the Asian genera Bassarona and Dophla.
6. (slang, usually in the plural) A fist.
   Put up your dukes!
   Your friend sure knows how to use his dukes. Biff, bang! One, two, and the copʼs on his ass! 1952, Ralph Ellison, Invisible Man, Penguin Books (2014), page 438
   "How did the sport go." "O sparred a few rounds. Let the instructor have a few on the button." "You must be tough." "I can handle my dukes." 1963, J P Donleavy, A Singular Man, published 1963 (USA), page 19

verb

1. (transitive, informal) To hit or beat with the fists.
   It seems that PI Rainer was duked by his wife […]. 2003, John A. Dinan, Private Eyes in the Comics, page 65
2. (slang, transitive) To give cash to; to give a tip to.
   I duked him twenty dollars.