a swimming kick used while treading water
"After slipping under the waves, I had to start thrashing my legs furiously just to stay above the surface."
A beat or blow; the sound of beating.
"The rhythmic thrash of rain against the windowpane filled the room until morning."
move or stir about violently
"The feverish patient thrashed around in his bed"
dance the slam dance
"After the heavy rain, the crowd thrashed through the mud in a wild celebration at the festival."
beat so fast that (the heart's) output starts dropping until (it) does not manage to pump out blood at all
"After hours of intense sprinting, my heart began to thrash against my ribs so violently that I suddenly felt dizzy and couldn't catch a breath."
move data into and out of core rather than performing useful computation
"The system is thrashing again!"
To beat mercilessly.
"The coach made the rookie run suicides until he was completely exhausted, effectively thrashing him to teach a lesson about discipline."
A surname.
"The local history club recently invited a Mr. Thrash to give a lecture on 19th-century maritime trade routes."