Words at Play : Top 10 Words from Trademarks, Vol. 2
When an Australian businessman invented this toy in the 1950s, he used a modern material – plastic – to update the ancient activity of playing with hoops.
His product took off, in part because of a catchy brand name that evoked the hip-swiveling hula dance associated with Hawaii, the U.S. territory that was about to become a state.
The word remains a trademark of WHAM-O, but is now widely used for any "plastic toy hoop that is twirled around the body."