thrash about

Also, thrash around. Move wildly or violently, as in He thrashed about all night, unable to sleep, or The fish thrashed around on the dock, so Meg threw it back in the water. [Mid-1800s]

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.