neptunium

noun
nep·tu·ni·um | \nep-ˈtü-nē-əm, -ˈtyü-\

Definition of neptunium 

: a radioactive metallic element that is chemically similar to uranium and is obtained in nuclear reactors especially as a by-product in the production of plutonium — see Chemical Elements Table

First Known Use of neptunium

1941, in the meaning defined above

History and Etymology for neptunium

New Latin, from International Scientific Vocabulary Neptune

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The first known use of neptunium was in 1941

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More Definitions for neptunium

neptunium

noun
nep·tu·ni·um | \nep-ˈtü-nē-əm, -ˈtyü-\

Kids Definition of neptunium

: a radioactive chemical element similar to uranium

neptunium

noun
nep·tu·ni·um | \nep-ˈt(y)ü-nē-əm \

Medical Definition of neptunium 

: a radioactive metallic element that is chemically similar to uranium and is obtained in nuclear reactors as a by-product in the production of plutonium symbol Np — see Chemical Elements Table

More from Merriam-Webster on neptunium

Britannica.com: Encyclopedia article about neptunium

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