ATOMIC NUMBER 99

 I. (noun) 

Sense 1

Meaning:

A radioactive transuranic element produced by bombarding plutonium with neutrons

Synonyms:

atomic number 99; E; einsteinium; Es

Classified under:

Nouns denoting substances

Hypernyms ("atomic number 99" is a kind of...):

metal; metallic element (any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.)

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