any of the small bodies, often remnants of comets, traveling through space: when such a body enters the earth's atmosphere it is heated to luminosity and becomes a meteor.
Origin of meteoroid
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
any of the small celestial bodies that are thought to orbit the sun, possibly as the remains of comets. When they enter the earth's atmosphere, they become visible as meteors
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Online Etymology Dictionary, © 2010 Douglas Harper
A small, rocky or metallic body revolving in interplanetary space around the Sun. A meteoroid is significantly smaller than an asteroid, ranging from small grains or particles to the size of large boulders. The clustered meteoroids associated with regular annual meteor showers are believed to be very small particles of cometary debris. Meteoroids that survive their passage through the Earth's atmosphere and land as meteorites are somewhat larger, solitary bodies and are encountered in no predictable pattern. See Note at meteor.
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