Watches don't say 'waterproof' anymore because of a legal battle which started in the 60's I believe regarding the failure of a watch and a claim against the manufacturer.
I get asked about this all of the time so here is a quick synopsis put together from a US site.
Waterproof: This is the supposed capability to completely exclude the possibility of water entering into any working portion of a watch. According to the Federal Trade Commission, no watch is 100 percent waterproof. Watches sold in the United States can only be referred to as "water resistant."
Water resistant: A watch that is described simply as "water resistant" can handle light moisture, such as a rainstorm or splashes from a sink, but it should not be completely submerged in water for any length of time.
Some watches are designed to be submerged, and these watches will state a specific depth such as "water resistant to 50 meters." Some watches measure water resistance in atmospheres (ATM); one atmosphere is equal to 10 meters of water pressure.
Watches can come in many different resistant depths:
Water Resistant (no depth indicated)Watch can handle light moisture but should not be submerged.
Water Resistant to 50/100/150 Meters (165 to 490 feet)Watch can be worn swimming, snorkelling, etc.
Water Resistant to 200 Meters (660 feet)Generally the accepted minimum standard for dive watches.
I will add more as I go!
AL