A blob of lava that was ejected while viscous and obtained a rounded or aerodynamic shape while in flight.
a rock that was twisted and shaped during eruption
Material thrown out of a volcano by explosions and landing on the sides of the mountain or in the surrounding area. Some bombs are merely solid blocks thrown out. If a mass of molten lava is thrown high into the air, it may become plastic before hitting the ground, forming a 'cow-pat' bomb. If it solidifies further while in the air it may take on a 'raindrop' shape, and if it is spinning, form a spiral tail. this is a 'spindle' bomb. Finally, if the lava thrown up is already starting to solidify, it will form a crust as it travels through the air. The continued expansion of the material inside this crust causes it to crack in patterns much like that on the crust of a baked loaf. These are 'bread-crust' bombs.
A blob of lava which is shot out of a volcano and falls back to the surface as a solidifying mass May be up to several cubic metres in diameter.
a piece of lava, often large and hollow, ejected by a volcano in eruption. [AHDOS
A volcanic bomb is a globule of molten rock (tephra) larger than 65 mm (2.5 inches) in diameter, formed when a volcano ejects viscous fragments of lava during an eruption. They cool into solid fragments before they reach the ground. Lava bombs can be thrown many kilometres from an erupting vent, and often acquire aerodynamic shapes during their flight.