astatine as·ta·tine (ās'tə-tēn', -tĭn)
A radioactive halogen element. Its longest lived isotope has a mass number of 210 and a half-life of 8.1 hours. Atomic number 85; melting point 302°C; boiling point 337°C; valence probably 1, 3, 5, 7.
Dictionary.com presents 366 FAQs, incorporating some of the frequently asked questions from the past with newer queries.