mercurial

mastery
UK /məːˈkjʊə.ɹɪ.əl/ US /mɝˈkjʊ.ɹi.əl/adjnoun

card 1 of 9 · context meaning

What does 'mercurial' mean in this sentence?

The alchemist carefully handled the mercurial substance, noting its silvery, liquid appearance.