ATOMIC NUMBER 89

 I. (noun) 

Sense 1

Meaning:

A radioactive element of the actinide series; found in uranium ores

Synonyms:

Ac; actinium; atomic number 89

Classified under:

Nouns denoting substances

Hypernyms ("atomic number 89" is a kind of...):

chemical element; element (any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter)

Holonyms ("atomic number 89" is a substance of...):

uranium ore (any ore from which uranium can be extracted)

Credits