'Flail' definitions:

Definition of 'flail'

(from WordNet)
noun
An implement consisting of handle with a free swinging stick at the end; used in manual threshing
verb
Give a thrashing to; beat hard [syn: thrash, thresh, lam, flail]
verb
Move like a flail; thresh about; "Her arms were flailing" [syn: flail, thresh]

Definition of 'Flail'

From: GCIDE
  • Flail \Flail\, n. [L. flagellum whip, scourge, in LL., a threshing flail: cf. OF. flael, flaiel, F. fl['e]au. See Flagellum.]
  • 1. An instrument for threshing or beating grain from the ear by hand, consisting of a wooden staff or handle, at the end of which a stouter and shorter pole or club, called a swipe, is so hung as to swing freely. [1913 Webster]
  • His shadowy flail hath threshed the corn. --Milton. [1913 Webster]
  • 2. An ancient military weapon, like the common flail, often having the striking part armed with rows of spikes, or loaded. --Fairholt. [1913 Webster]
  • No citizen thought himself safe unless he carried under his coat a small flail, loaded with lead, to brain the Popish assassins. --Macaulay. [1913 Webster]

Synonyms of 'flail'

From: Moby Thesaurus