thresh

verbs

move or stir about violently
"The feverish patient thrashed around in his bed"
convulse, jactitate, slash, thrash, thrash about, thresh, thresh about, toss
move like a flail; thresh about
"Her arms were flailing"
flail, thresh
beat the seeds out of a grain
thrash, thresh
is derived from
thresher
is derived from
threshing
give a thrashing to; beat hard
flail, lam, thrash, thresh