Synonyms for Thresh (same or very similar meaning)
WordNet sense 1 (move like a flail; thresh about):
flail
WordNet sense 2 (move or stir about violently):
convulse, slash, thrash, toss, jactitate, thrash about, thresh about
WordNet sense 3 (give a thrashing to; beat hard):
lam
From the ODE community, based on WordNet
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