a bright metallic element found in zirconium ores: used in tungsten filaments and as a neutron absorber in nuclear reactors. Symbol: Hf; atomic no: 72; atomic wt: 178.49; valency: 4; relative density: 13.31; melting pt: 2231±20°C; boiling pt: 4603°C
Word origin
C20: New Latin, named after Hafnia, Latin name of Copenhagen + -ium
hafnium in American English
(ˈhæfniəm)
noun
a metallic chemical element found with, and similar to, zirconium: used in the manufactureof light-bulb filaments and in reactor control rods: symbol, Hf; at. no., 72
Word origin
ModL: so named (1923) by D. Coster (1889-1950), Du chemist, and G. C. de Hevesy (c. 1889-1966), Hung chemist, after Hafnia, Latinized name of Dan København, Copenhagen, where it was discovered + -ium
Examples of 'hafnium' in a sentence
hafnium
They're made of some stuff called hafnium, which absorbs the neutrons, stops the reaction running out of control.