Dictionary flailSwing wildly

verb

flail

FLAYL/fleɪl/

To wave or swing wildly and without control.

The skater's arms flail as he loses his balance.

An off-balance roller skater swings both arms as his skates splay apart.

Etymology

flagellumLate Latina winnowing tool or flail

The motion of whipping or moving like a flail broadened to any wild, uncontrolled swinging.

More examples

Branches flail in the strong wind.
He began to flail for something to grasp.

Forms

flail

Similar words

thrash: Suggests forceful repeated uncontrolled movement.
wave: Does not necessarily imply loss of control.