From Middle English flayle, from earlier fleil, fleyl, fleȝȝl, from Old English fligel, *flegel (“flail”), from Proto-West Germanic *flagil, of uncertain origin. Cognate with Scots flail (“a thresher's flail”), West Frisian fleil, flaaiel (“flail”), Dutch vlegel (“flail”), German Flegel (“flail”). Possibly a native Germanic word from Proto-Germanic *flagilaz (“whip”), from Proto-Germanic *flag-, *flah- (“to whip, beat”), from Proto-Indo-European *pleh₂k- (“to beat, hit, strike; weep”); compare Old Norse flaga (“sudden attack, bout”), Lithuanian plàkti (“to whip, lash, flog”), Ancient Greek πληγνύναι (plēgnúnai, “strike, hit, encounter”), Latin plangō (“lament”, i.e. “beat one's breast”) + Proto-Germanic *-ilaz (instrumental suffix). If so, related also to English flag, flack, flacker. Alternatively, Proto-West Germanic *flagil may be an early borrowing of Latin flagellum (“winnowing tool, thresher”), diminutive of flagrum (“scourge, whip”), from Proto-Indo-European *bʰlag-, *bʰlaǵ- (“to beat”); compare Old Norse blekkja (“to beat, mistreat”). Compare also Old French flael (“flail”), Walloon flayea (“flail”) (locally pronounced "flai"), Italian flagello (“scourge, whip, plague”).
1
A tool used for threshing, consisting of a long handle (handstock) with a shorter stick (swipple or swingle) attached with a short piece of chain, thong or similar material.
When in one night, ere glimpse of morn, His shadowy flail hath threshed the corn That ten day-labourers could not end;1631, John Milton, L'Allegro:
Huge fragments vaulted like rebounding hail, Or chaffy grain beneath the thresher's flail1816, Samuel Taylor Coleridge, Kubla Khan:
2 more examples
On him alone the curse of Cain Fell, like a flail on the garnered grain, And struck him to the earth!1842, Henry Wadsworth Longfellow, The Slave in the Dismal Swamp:
If the farmer must use the spade because he has not capital enough for a plough, the sickle instead of the reaping machine, the flail instead of the thresher...1879, Henry George, chapter V, in Progress and Poverty:
2
A weapon which has the (usually spherical) striking part attached to the handle with a flexible joint such as a chain.
3
Often Part of a rotating device, often used for cutting vegetation.
The carriage washing plant uses four pairs of rotating rag flails and will be capable of dealing with the whole of the diesel units as well as steam stock used for main-line trains.1957 December 23, “Diesel Depot for Darlington”, in Railway Magazine, page 876:
From Middle English flayle, from earlier fleil, fleyl, fleȝȝl, from Old English fligel, *flegel (“flail”), from Proto-West Germanic *flagil, of uncertain origin. Cognate with Scots flail (“a thresher's flail”), West Frisian fleil, flaaiel (“flail”), Dutch vlegel (“flail”), German Flegel (“flail”). Possibly a native Germanic word from Proto-Germanic *flagilaz (“whip”), from Proto-Germanic *flag-, *flah- (“to whip, beat”), from Proto-Indo-European *pleh₂k- (“to beat, hit, strike; weep”); compare Old Norse flaga (“sudden attack, bout”), Lithuanian plàkti (“to whip, lash, flog”), Ancient Greek πληγνύναι (plēgnúnai, “strike, hit, encounter”), Latin plangō (“lament”, i.e. “beat one's breast”) + Proto-Germanic *-ilaz (instrumental suffix). If so, related also to English flag, flack, flacker. Alternatively, Proto-West Germanic *flagil may be an early borrowing of Latin flagellum (“winnowing tool, thresher”), diminutive of flagrum (“scourge, whip”), from Proto-Indo-European *bʰlag-, *bʰlaǵ- (“to beat”); compare Old Norse blekkja (“to beat, mistreat”). Compare also Old French flael (“flail”), Walloon flayea (“flail”) (locally pronounced "flai"), Italian flagello (“scourge, whip, plague”).
1
To beat using a flail or similar implement.
2
To wave or swing vigorously
Tangling with Ziv, Cameron caught him with a flailing elbow, causing the Israeli defender to go down a little easily. However, the referee was in no doubt, much to the displeasure of the home fans.2011 October 20, Michael da Silva, “Stoke 3 - 0 Macc Tel-Aviv”, in BBC Sport:
He stopped in his tracks – then, flailing his arms wildly in the air, began to stagger backwards.1937, H. P. Lovecraft, The Evil Clergyman:
3
To thresh.
4
To move like a flail.
He was flailing wildly, but didn't land a blow.
Undismayed he continued to flail with the broken half of it, denting many a helmet[.]1966, James Workman, The Mad Emperor, Melbourne, Sydney: Scripts, page 46: