The crossword solution for the term 'Volcano Stuff' is 'ASH', which is a three-letter word. ASH is a type of material that is created when a volcano erupts and is composed of tiny fragments of rock, minerals, and glass. It is usually gray or black in color and can be found near volcanoes or in the atmosphere after an eruption. ASH is also used in many industries, such as construction, agriculture, and manufacturing.