Ejecta is the scientific term for material that is thrown or forced out due to an eruption, explosion, or impact. When a star explodes, the matter that is thrown out from the center is called ejecta.
A volcano casts out molten ejecta in the form of lava bombs. Other volcanic ejecta includes ash, dust, and rock fragments. When a large meteorite from space hits Earth's surface, the impact sends a spray of pulverized rock and debris outwards. That ejecta settles around a newly created crater. Human activity can create ejecta, too. When bombs are detonated, massive amounts of ejecta in the form of soil and rock fragments are displaced and launched outward and upward.