exercise ball

noun

1. a firm, very large, usually inflatable ball used in various exercises, chiefly to strengthen the back, pelvis, and abdominal muscles.

Word History and Origins

Origin of exercise ball¹

First recorded in 1905–10

Example Sentences

Place one heel on top of an exercise ball and raise your other leg straight up, slightly bending your knee.

From Outside Online

If you sit all day, consider swapping your desk chair for an exercise ball, or take phone calls pacing around your office.

From The Daily Beast