su·​per·​heavy | \ ˌsü-pər-ˈhe-vē How to pronounce superheavy (audio) \

Definition of superheavy

: extremely heavy superheavy furniture superheavy traffic a superheavy discussion with his mother especially, chemistry : relating to or being a chemical element with a greater atomic mass than that of uranium The existence of superheavy elements, those with many more protons than uranium (proton number 92), was predicted more than 40 years ago. — Georg Bollen

Other Words from superheavy

superheavy noun, plural superheavies
In February the world was treated to a transcontinental eureka moment: Scientists … announced they had discovered two new chemical elements. Called superheavies because of their large atomic mass, elements 113 and 115 lasted little more than a second. — Elizabeth Svoboda

First Known Use of superheavy

1822, in the meaning defined above

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The first known use of superheavy was in 1822

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Cite this Entry

“Superheavy.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2020.

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