Oort Cloud · proper noun1
Named after the Dutch astronomer Jan Hendrik Oort, who revived the Estonian astronomer Ernst Öpik’s idea from 1932 of a reservoir of long-period comets in the form of an orbiting cloud at the outermost edge of the Solar System in 1950 to resolve a paradox about the origin of comets.
Oort cloud · proper noun, noun2
A cloud-like structure, named after Dutch astronomer Jan Oort, who proposed it.
Etymology from Wiktionary, CC BY-SA 4.0.