po·lo·ni·um 
(pə-lōnē-əm)
(pə-lōnē-əm)n. Symbol Po
A radioactive metallic element, occurring naturally in small quantities as a product of radium disintegration and produced synthetically by bombarding bismuth or lead with neutrons. Most isotopes decay by alpha-particle emission; the most stable are Po-208 and Po-209, with half-lives of 2.9 years and 102 years, respectively. Po-210, with a half-life of 138.4 days, is the most readily available isotope and is extremely toxic. Atomic number 84; melting point 254°C; boiling point 962°C; specific gravity 9.20; valence 2, 4, 6. See Periodic Table.
[From Medieval Latin Polōnia, Poland (the native country of Marie Curie, who discovered this element along with her husband Pierre).]
- solid propellant
- solid solution
- solid-state
- solid-state drive
- solid-state physics
- solidus
- solifluction
- Solihull
- soliloquist
- soliloquize
- soliloquizer
- soliloquy
- Solingen
- solipsism
- solipsist
- solipsistic
- solitaire
- solitarily
- solitariness
- solitary
- solitary confinement
- soliton
- solitude
- solitudinarian
- solleret