ionium

[ ahy-oh-nee-uh m ]
/ aɪˈoʊ ni əm /

noun Chemistry.

a naturally occurring radioactive isotope of thorium. Symbol: Io; atomic number: 90; atomic weight: 230.

Origin of ionium

First recorded in 1905–10; ion + -ium

Words nearby ionium

ionian islands, ionian mode, ionian sea, ionic, ionic bond, ionium, ionization, ionization chamber, ionization or ionizing, ionization potential, ionize

Example sentences from the Web for ionium

  • Ionium expels an alpha particle and becomes radium, which is a bivalent element resembling barium belonging to the second group.

    A Brief Account of Radio-activity |Francis Preston Venable

British Dictionary definitions for ionium

ionium
/ (aɪˈəʊnɪəm) /

noun

obsolete a naturally occurring radioisotope of thorium with a mass number of 230 Symbol: Io

Word Origin for ionium

C20: from New Latin, from ion + -ium