*flounc*

v. i. [ imp. & p. p. Flounced p. pr. & vb. n. Flouncing ] [ Cf. OSw. flunsa to immerge. ] To throw the limbs and body one way and the other; to spring, turn, or twist with sudden effort or violence; to struggle, as a horse in mire; to flounder; to throw one's self with a jerk or spasm, often as in displeasure. [ 1913 Webster ]

To flutter and flounce will do nothing but batter and bruise us. Barrow. [ 1913 Webster ]

With his broad fins and forky tail he laves
The rising sirge, and flounces in the waves. Addison. [ 1913 Webster ]