[ rent-gen-ee-uhm, -jen-, ruhnt- ]
/ rɛntˈgɛn i əm, -ˈdʒɛn-, rʌnt- /
noun Chemistry, Physics.
a superheavy, synthetic radioactive element with a very short half-life. Symbol: Rg; atomic number: 111.
BEAT THE DOLDRUMS WITH THIS WORD OF THE DAY QUIZ!
We know you’ll tackle this quiz totis viribus! See how many words from the week of Oct 12–18, 2020 you get right!
Question 1 of 7
What does “Indigenous” mean?
Formerly u·nu·nun·i·um [uh-nuh-nuhn-ee-uhm], /ə nəˈnʌn i əm/, el·e·ment 111 .
Origin of roentgenium
First recorded in 2000–05; named after German physicist Wilhelm Konrad Roentgen.
Words nearby roentgenium
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020
Scientific definitions for roentgenium
[ rĕnt-gĕn′ē-əm, -jĕn′-, rŭnt-, rœnt-gĕn′- ]
An artificially produced radioactive element with a mass number of 280. Its most stable known isotope has a half-life of 3.6 seconds. Atomic number 111. See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.