Oort cloud

noun

: 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

Word History

Etymology

Jan Oort †1992 Dutch astronomer

First Known Use

1974, in the meaning defined above

Time Traveler
The first known use of Oort cloud was in 1974

Dictionary Entries Near Oort cloud

Cite this Entry

“Oort cloud.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Oort%20cloud. Accessed 30 Nov. 2022.

Kids Definition

Oort cloud

noun

: a spherical shell of small icy bodies (as comets) that orbit the sun far beyond Pluto

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