a brand of personal watercraft.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
trademark a small self-propelled vehicle for one person resembling a scooter, which skims across water on a flat keel, and is steered by means of handlebars
verb jet-ski -skis, -skiing, -skied or -ski'd (intr; usually not capital)
to ride a Jet Ski
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012