Related Clues:

• C-cacophonous cautionary condition
• Mass of airborne water vapour
• Mass of water droplets
• Mushroom ___ (atom bomb's wake)
• Make murky
• Fluffy floater
• It's dark when raining
• It hides the sun
• Become gloomy, as stupid person going round university
• The Temptations' was numbered nine
• Become less transparent
• Visible vapour in sky
• Make less transparent
• Nebula
• Source of rain