ionium
/ʌɪˈəʊnɪəm/Chemistry
noun
A radioactive isotope of thorium with mass number 230, produced by the alpha decay of uranium-234 and decaying in turn to radium-226 with a half-life of 75,000 years. Symbols Io, 230Th.
Origin
Early 20th century. From ion + -ium. With the semantic motivation, compare quot. 1907.
- seminarist
- seminary
- seminiferous
- Seminole
- semiochemical
- semi-official
- semi-officially
- semiological
- semiologist
- semiology
- semi-opaque
- semi-opera
- semiosis
- semiotic
- semiotical
- semiotically
- semiotician
- semiotics
- Semipalatinsk
- semipalmated
- semi-Pelagian
- semi-Pelagianism
- semi-permanent
- semi-permanently
- semipermeable