Oort cloud

noun
\ ˈȯrt- How to pronounce Oort cloud (audio) \

Definition of Oort cloud

: a spherical shell of cometary bodies believed to surround the sun far beyond the orbits of the outermost planets and from which some are dislodged when perturbed to fall toward the sun — compare kuiper belt

First Known Use of Oort cloud

1974, in the meaning defined above

History and Etymology for Oort cloud

Jan Oort †1992 Dutch astronomer

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