[Pigments] ultramarine, smalt, cobalt, cyanogen [Chem]; Prussian blue, syenite blue†; bice†, indigo; zaffer†. lapis lazuli, sapphire, turquoise; indicolite†. blueness, bluishness; bloom. Adj. blue, azure, cerulean; sky-blue, sky-colored, sky-dyed; cerulescent†; powder blue, bluish; atmospheric, retiring; cold.