a mixture of neodymium and praseodymium, formerly thought to be an element. Symbol: Di.
Origin
< Neo-Latin < Greekdídym(os) twin (see didymous) + -ium; so named by Swedish chemist Carl Mosander (1797-1858), who discovered it in 1843, from its close association with lanthanum
Examples from the web for didymium
He named the element didymium, as it was an inseparable twin brother of lanthanum.
British Dictionary definitions for didymium
didymium
/daɪˈdɪmɪəm; dɪ-/
noun
1.
a mixture of the metallic rare earths neodymium and praseodymium, once thought to be an element
2.
a mixture of rare earths and their oxides used in colouring glass
Word Origin
C19: from New Latin, from Greek didumos twin + -ium