superheavy
adjective
su·per·heavy
| \ ˌsü-pər-ˈhe-vē
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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