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Oort cloud
Oort cloud [ áwrt klòwd ]


noun 
Definition:
 
collection of comets: a huge, roughly spherical, orbiting collection of comets thought to exist at the edge of the solar system
[Late 20th century. After Jan Hendrix Oort (1900-1992), Dutch astronomer]
Encarta® World English Dictionary [North American Edition] © & (P)2009 Microsoft Corporation. All rights reserved. Developed for Microsoft by Bloomsbury Publishing Plc.
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