[ yoo-ni-lok-tee-uh m ]
/ ˌyu nɪˈlɒk ti əm /

noun Chemistry, Physics.

former name of hassium. Symbol: Uno
Also called element 108.

Definition for unniloctium (2 of 3)

[ has-ee-uh m ]
/ ˈhæs i əm /

noun Chemistry, Physics.

a superheavy, synthetic, radioactive element with a very short half-life. Symbol: Hs; atomic number: 108.

Origin of hassium

after Medieval Latin Hassia (the German state of Hesse, location of the institute where it was first created); see -ium
Formerly unniloctium, element 108.

Definition for unniloctium (3 of 3)

element 108

noun Chemistry, Physics.

Formerly unniloctium.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for unniloctium

/ (ˈhæsɪəm) /


a synthetic element produced in small quantities by high-energy ion bombardment. Symbol: Hs; atomic no: 108

Word Origin for hassium

C20: from Latin, from Hesse, German state where it was discovered
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for unniloctium

[ häsē-əm ]


A synthetic, radioactive element that is produced by bombarding lead with iron ions. Its known isotopes have mass numbers ranging from 263 to 277. Hs 277 has the longest confirmed half-life (16.5 minutes). Atomic number 108. See Periodic Table.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.