No, it means that the product resists water better than products than regular sunscreen products. The FDA (U.S. Foods and Drugs Administration) has specifically removed the term “waterproof” off of the labels of sunscreens because this is a misleading term. Most labels in the U.S. for these products should either be 40 minute or 80 minute water resistant.
Sun exposure and water exposure both degrade the effectiveness of sunscreens, and this is no different with water resistant products. Water resistant products can shrug off some sweat and a bit of liquid splashes well, but after a swim, it is a good idea to reapply the product. All sunscreens should be reapplied every 2 hours if you are still being exposed to the sun.