'francium' definitions:
Definition of 'francium'
From: WordNet
noun
A radioactive element of the alkali-metal group discovered as a disintegration product of actinium [syn: francium, Fr, atomic number 87]
Definition of 'francium'
From: Elements
- Symbol: Fr
- Atomic number: 87
- Atomic weight: (223)
- Radioactive element, belongs to group 1 of the periodic table. Found in uranium and thorium ores. The 22 known isotopes are all radioactive, with the most stable being Fr-223. Its existence was confirmed in 1939 by Marguerite Perey.