fan

Etymology 1

From Middle English fan, from Old English fann (“a winnowing, fan”), from Latin vannus (“fan for winnowing grain”), from Proto-Indo-European *h₂weh₁- (“to blow”). Cognate with Latin ventus (“wind”), Dutch wan (“fan”), German Wanne (“winnowing basket”), Swedish vanna (“a fan for winnowing”), Old English windwian (“to fan, winnow”). More at winnow.

noun

1. A hand-held device consisting of concertinaed material, or slats of material, gathered together at one end, that may be opened out into the shape of a sector of a circle and waved back and forth in order to move air towards oneself and cool oneself.
2. An electrical or mechanical device for moving air, used for cooling people, machinery, etc.
3. The action of fanning; agitation of the air.
   "If I cannot be of service, then I certainly don't wish to impose," said McGinty, with a quick fan of breeze that indicated a sweeping bow. 1998, Brock Thoene, Bodie Thoene, A New Frontier: Saga of the Sierras, page 181
4. Anything resembling a hand-held fan in shape, e.g., a peacock’s tail.
5. An instrument for winnowing grain, by moving which the grain is tossed and agitated, and the chaff is separated and blown away.
6. A small vane or sail, used to keep the large sails of a smock mill always in the direction of the wind.
7. (mathematics) A section of a tree having a finite number of branches

verb

1. (transitive) To blow air on (something) by means of a fan (hand-held, mechanical or electrical) or otherwise.
   We enjoyed standing at the edge of the cliff, being fanned by the wind.
   Alice took up the fan and gloves, and, as the hall was very hot, she kept fanning herself all the time she went on talking. 1865, Lewis Carroll, “The Pool of Tears”, in Alice's Adventures in Wonderland, London: MacMillan and Co., published 1866, page 19
2. (transitive) To slap (a behind, especially).
   Part of it was that as much as I respected filial devotion and as much as I liked Sarah Barstow, it would have been a real satisfaction to put her across my knees and pull up her skirts and giver her a swell fanning, for not taking a look at that driver. 1934, Rex Stout, Fer-de-Lance, Bantam, published 1992, page 148
3. (intransitive, usually to fan out) To move or spread in multiple directions from one point, in the shape of a hand-held fan.
4. (transitive) To dispel by waving a hand-held fan.
   I attempted to fan the disagreeable odour out of the room.
5. (firearms, transitive) To perform a maneuver that involves flicking the top rear of an old-style gun.
   To fan a single action revolver, hold down the trigger and strike the hammer repeatedly with a free hand. 2011, Hans-Christoan Vortisch, GURPS Tactical Shooting, page 14
6. (figurative) To invigorate, like flames when fanned.
   She comes, to fan my ardour, She kills me with her kisses. 1923, Arthur Symons, Love's Cruelty, page 43
7. To winnow grain.
   By the first article, these fanning mills were appointed to be sent to the proprietors of the mills of Sault-à-la puce, Petit-Pré, Beauport, Pointe de Lévy, St. Nicolas and Ste. Famille in the isle of Orleans " to have all the wheat in general of whatever quality sent to these mills passed and fanned, before converting them into flour." 1856, François Réal Angers Lelièvre, Lower Canada reports
8. (rail transport, transitive) To apply (the air brake) many times in rapid succession.
   Fanning the brakes results in the gradual depletion of the pressure in the cars' brake reservoirs, which can eventually cause a loss of all braking.
9. (baseball, intransitive) To strike out.
10. (baseball, transitive) To strike out (a batter).

Etymology 2

Clipping of fanatic, originally in US baseball slang. Possibly influenced by fancy (“group of sport or hobby enthusiasts”), i.e. fancy boy (“fan”).

noun

1. A person who is fond of something or someone, especially an admirer of a performer or aficionado of a sport.
   I am a big fan of libraries.

Etymology 3

From Cantonese 分. Doublet of fen and hoon.

noun

1. (Hong Kong, dated) A unit of length, equivalent to 0.1 tsun (0.01 chek), or 0.00371475 metres.
   1 chek (foot) = 14⅝ English inches divided into 10 tsün (inches) and each tsün into ten fan or tenths. 1939, chapter XI, in Colonial Reports - Annual Issues, page 37