a bright, silvery chemical element, one of the rare-earth elements: symbol, Tm; at. no. 69
Origin of thuliumModern Latin from thulia (from which it was isolated in 1879) + -ium: so named (1886) by L. de Boisbaudran (see gadolinium)
A bright, soft, silvery, metallic element of the lanthanide series obtained commercially from the mineral monazite, having an x-ray emitting isotope that is used in portable medical x-ray units. Atomic number 69; atomic weight 168.934; melting point 1,545°C; boiling point 1,950°C; specific gravity 9.321 (at 25°C); valence 2, 3. See Periodic Table.
Origin of thuliumAfter Thule 1
- A metallic chemical element (symbol Tm) with an atomic number of 69.
Thule (as a poetic way to say Scandinavia) + -ium