radioactinium
American
[rey-dee-oh-ak-tin-ee-uhm]
/ ˌreɪ di oʊ ækˈtɪn i əm /
noun
Chemistry.
Etymology
Origin of radioactinium
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
