FRANCIUM

francium, Fr, atomic number

(noun) a radioactive element of the alkali-metal group discovered as a disintegration product of actinium

Source: WordNet® 3.1

Etymology

Noun

francium (usually uncountable, plural franciums)

The chemical element (symbol Fr) with an atomic number of 87. It is an intensely radioactive alkali metal that is not found in nature.

(countable) A single atom of this element.

Synonyms

• actinium-K (obsolete)

• virginium (obsolete)

Source: Wiktionary