Oort

British

/ ɔːt /

noun

Jan Hendrick. 1900–92, Dutch astronomer, who confirmed (1927) and developed the theory of galactic rotation. He was the first to propose (1950) the existence of a mass of comets orbiting the sun far beyond the orbit of Pluto (the Oort cloud )

"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

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Oort

The Oort Cloud does not yet show up on Google Maps, but it’s out there, a realm of icy objects and comets, trillions of them, far beyond the orbit of Neptune.

From Slate ● Dec. 9, 2025

And when people are ogling the night sky this week, they should also keep an eye out for two additional celestial sightings — Saturn and the appearance of an ancient Oort cloud comet, she added.

From Los Angeles Times ● Oct. 16, 2024

The Oort Cloud, a hypothesized shell of icy worlds at an unfathomable distance from the sun, has never been directly seen—and VRO won’t change that.

From National Geographic ● Jan. 9, 2024

Given the size and distance of the Oort cloud, though, we may never know for sure what's lurking out there.

From Scientific American ● Jun. 28, 2023

But let’s pretend again that we have made it to the Oort cloud.

From "A Short History of Nearly Everything" by Bill Bryson

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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023