Found this on-line:
"Sport watches cover a wide range of functions. Some sports watches are specifically targeted to sports including sailing watches, referee timers and running watches. Others are dedicated to outdoor pursuits with high levels of water resistance, barometers, thermometers and other useful features. Sports watches also include the many chronographs that have stopwatch functionality and can be used to time events to varying levels of accuracy, many chronographs are allied with high achiever sporting events such as Casio Edifice and the Formula 1 Red Bull Racing team or Seiko and the Barcelona Football club."
That covers just about any watch with a timing or other sports related function. That's quite a large section of the market, so I'm not sure it's a useful term. It's certainly not one that I use.