ac·tin·o·u·ra·ni·um
(ăk-tĭn′ō-yo͝o-rā′nē-əm, ăk′tə-nō-)n. The isotope of uranium with mass number 235, fissionable with slow neutrons.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
actinouranium
(ˌæktɪnəʊjʊˈreɪnɪəm) n (Elements & Compounds) the isotope of uranium that has a mass number of 235
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
uranium 235
n. the radioactive uranium isotope having a mass number of 235 and that undergoes fission with a release of energy when bombarded with neutrons.
[1935–40]
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