It says "water resistant", but can I swim with it ?

It says "water resistant", but can I swim with it ?

Water resistance is measured in bars (unit of pression, 1 bar being equivalent to 1 atmosphere), and watches are tested at these pressures for certain period of time. Exceptional pressure, as when diving, may exceed those limits, so if you are a keen diver you will need a watch that can tolerate that pounding.
Translation varies and your best guide is your supplier as it will almost certainly be part of the guaranteee.

Manufacturers often measure water resistance to a number of feet (ft), meters (m) or atmospheres (atm). Watches marked "water resistant" with or without additional indication of high pressure must comply with NIHS 92-10 watch Standard (corresponding to ISO 2281 international Standard). Such watches are designed for everyday life and must be water resistant during exercices such as short swimmings. They can be worn in different temperature and pressure conditions but are under no circumstances designed for scuba diving.

Divers' watches must be water resistant at 330 ft minimum. They must also feature a time controller and comply with standards provided by NIHS 92-11 (ISO 6425) : luminosity, shock resistance, anti-magnetism, band solidity.

Remember that if you are going to be moutain climbing, parachuting, sky diving, hang gliding, or skiing, it is advisable to use a watch that is atm damage-protected as pressures change both above and below sea level.

For regular water use, solid metal cases or specially constructed products are recommended, including screwed-in case backs and crowns.
Do not hesitate to ask your next dealer about water resistance functions, and remember that only professional changing battery will guarantee the seals and thus the water resistance of your timepiece.