/ Dictionary / Index A actinouranium: Meaning and Definition of Find definitions for: ac•tin•o•u•ra•ni•um Pronunciation: (ak-tin"ō-yoo-rā'nē-um, ak"tu-nō-), [key] — n. Chem. See Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. actinotherapy actinozoan Related Content Daily Word Quiz: menagerie Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language