Jactitation is a noun that refers to the restless tossing of a body.
The Latin word jactare (jock TAR ay) means ’to toss.’ Its English variation has been around since the 16th century, getting most of its use in a medical context. Here’s an example:
All that jactitation I heard on the other side of the bed had me worried about my wife’s health. But it turned out all that tossing and turning didn’t come from her. It was just our Golden Retriever, Rex joining us in the middle of the night.