Astrophysicists say it was a bolide, or a meteor that explodes in the air.
Some industrious Chelyabinsk citizen has already offered to sell a piece of the meteor for a souvenir.
The idea had a short but powerful resonance: why did the meteor explode above ground, people wondered?
late 15c., "any atmospheric phenomenon," from Middle French meteore (13c.) and directly from Medieval Latin meteorum (nominative meteora), from Greek ta meteora "the celestial phenomena, things in heaven above," plural of meteoron, literally "thing high up," noun use of neuter of meteoros (adj.) "high up, raised from the ground, hanging," from meta- "over, beyond" (see meta-) + -aoros "lifted, hovering in air," related to aeirein "to raise" (see aorta).
Specific sense of "fireball, shooting star" is attested from 1590s. Atmospheric phenomena were formerly classified as aerial meteors (wind), aqueous meteors (rain, snow, hail), luminous meteors (aurora, rainbows), and igneous meteors (lightning, shooting stars).
Our Living Language : The streaks of light we sometimes see in the night sky and call meteors were not identified as interplanetary rocks until the 19th century. Before then, the streaks of light were considered only one of a variety of atmospheric phenomena, all of which bore the name meteor. Rain was an aqueous meteor, winds and storms were airy meteors, and streaks of light in the sky were fiery meteors. This general use of meteor survives in our word meteorology, the study of the weather and atmospheric phenomena. Nowadays, astronomers use any of three words for rocks from interplanetary space, depending on their stage of descent to the Earth. A meteoroid is a rock in space that has the potential to collide with the Earth's atmosphere. Meteoroids range in size from a speck of dust to a chunk about 100 meters in diameter, though most are smaller than a pebble. When a meteoroid enters the atmosphere, it becomes a meteor. The light that it gives off when heated by friction with the atmosphere is also called a meteor. If the rock is not obliterated by the friction and lands on the ground, it is called a meteorite. For this term, scientists borrowed the -ite suffix used in the names of minerals like malachite and pyrite.
A version of COMIT with Lisp-like syntax, written in MIT Lisp 1.5 for the IBM 7090. "METEOR - A List Interpreter for String Transformation", D.G. Bobrow in The Programming Language LISP and its Interpretation, E.D. and D.G. Bobrow eds, 1964.