Noun
An oxide of holmium.
Source: Webster's dictionaryIn 1879, Swedish chemist Per Theodor Cleve separated in the rare earth erbia another two previously unknown components, which he called holmia and thulia : these were the oxides of holmium and thulium respectively. Source: Internet
The brown substance was the oxide of the element holmium and was named holmia by Cleve, and the green substance was the oxide of an unknown element. Source: Internet