The Clue Fog-like waterfall spray
The Answer MIST
The word "mist" refers to a fine spray of water droplets that can be found near waterfalls. When water cascades down, it creates a fog-like effect as the droplets scatter in the air. This mist can make the area around the waterfall feel cool and refreshing. Therefore, "mist" perfectly matches the clue "fog-like waterfall spray."