viridianPronunciation: /vɪˈrɪdɪən/Definition of viridian noun [mass noun] a bluish-green pigment consisting of hydrated chromium hydroxide. a bluish-green colour. Origin: late 19th century: from Latin viridis 'green' (from virere 'be green') + -ianviridian in other Oxford dictionaries Definition of viridian in the US English dictionary