The crossword solution for the term 'shower source' is 'CLOUD'. A CLOUD is a visible mass of condensed water droplets or ice crystals suspended in the atmosphere. Clouds form when air containing water vapor rises and cools to the point where the water vapor condenses into liquid droplets or ice crystals. These droplets and crystals form clouds, which are the primary source of precipitation such as rain, snow, hail, and sleet.