To flail is defined as to wave or swing about wildly or to flounder.(verb)
When you wave your arms around wildly, this is an example of flail.
The definition of a flail is a farm tool that is a long-handled stick that is swung to thresh grain.(noun)
An example of a flail is a tool used to toss grain up in the air.
See flail in Webster's New World College Dictionary
Origin: ME fleil < OFr flaiel & OE *flegel, both < L flagellum, a whip, scourge: see flagellate
transitive verb, intransitive verb
See flail in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English flegil
Origin: and from Old French flaiel
Origin: , both from Late Latin flagellum, threshing tool
Origin: , from Latin flagrum, whip.
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