1. Hydroplaning
    V. scary, threatening, life endangering. Sounds like something you'd do on a tropical vacation
  2. Spelunking
    This should be a synonym for frolicking. It feels so light and carefree. But it's actually all about exploring caves. Prolly still pretty fun.
  3. Water boarding
    Believe it or not, this isn't an aquatic sport
  4. Diphthong
    This is a grammar word, not some sort of undergarment. Where's the fun in that?
  5. Mastication
    It's chewing. Just chewing. Nothing else.