Devout Night Cerulean

From the Latin devotus, consecrated — used principally in religious contexts for the dignified deep colors of sacred art and ecclesiastical dress. As a color modifier, devout implies saturation combined with restraint: the deep blues of Marian mantles, the deep reds of cardinals' robes. Sits in the bold-and-formal corner alongside imperial.

Old English niht, darkness-and-sleep. As a color modifier, night implies a moonlit-or-star-lit-dark quality, the visual register of clear-sky moonlit-and-star-lit atmospheric Rayleigh-scattered low-light surfaces against deep blue-black night-sky horizon. Sits at the modifier-and-time end of the grid, parallel to eve and yore in usage.

From the Latin caeruleum, originally referring to dark blue paint pigment of the Roman world, then via French céruléen into English. As a modern art-supply name, cerulean blue is the cobalt-tin oxide pigment introduced in 1805. The color refers to a clean, slightly green-shifted blue with the matte finish of mineral pigment in linseed oil: lighter than cobalt, deeper than aqua, with the painter's weight of a word for sky.