īˈōnēəm noun
( -s )
Etymology: ion + -ium; so called from its ionizing action
: a naturally occurring radioactive isotope of thorium having mass 230 — symbol Th 230 or Io ; see uranium series
īˈōnēəm noun
( -s )
Etymology: ion + -ium; so called from its ionizing action
: a naturally occurring radioactive isotope of thorium having mass 230 — symbol Th 230 or Io ; see uranium series
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012