| NOUN | substance | francium, Fr, atomic number 87 | a radioactive element of the alkali-metal group discovered as a disintegration product of actinium |
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| Meaning | A radioactive element of the alkali-metal group discovered as a disintegration product of actinium. | |
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| Synonyms | Fr, atomic number 87 | |
| Broader | metallic element, metal | Any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc. |