MIST OR FOG is a type of atmospheric phenomenon that is composed of tiny water droplets suspended in the air. The crossword solution for this term is VAPOR, which is a gas or VAPOR composed of molecules in a state of very low density. Vapors are typically created when a liquid is heated and the molecules become energized, allowing them to escape into the atmosphere. MIST OR FOG is a common occurrence in many parts of the world, especially in areas with high humidity.