Definition of casual water in US English:

casual water

noun

Golf
  • Water that has accumulated temporarily and does not constitute a recognized hazard of the course. A player may move a ball from casual water without penalty.

    • ‘It had rained hard the night before the final round, and at the 12 th hole a player requested relief from casual water.’
    • ‘Your ball was in casual water, and you were entitled to relief without a penalty.’
    • ‘In the case of casual water, such as a small puddle caused by heavy rain, the area is an abnormal ground condition, and the player is entitled to place the ball at the nearest point of relief that is not in a hazard or closer to the hole.’
    • ‘It is either in a water hazard or in casual water overflowing the hazard.’
    • ‘If they're taking relief from an obstruction such as a cartpath or ground under repair or casual water, they don't know where to drop, either.’