Heavy Plumed Indigo

Old English hefig, weighty — cognate with heave. Used as a color modifier since at least the seventeenth century to indicate weight in saturation as much as value: heavy with pigment, heavy-bodied. In the engine's adjective grid, heavy sits alongside deep and plush in the dark-and-saturated quadrant. Closer to a fabric description than a pure value word.

Latin plūma, feather. As a color modifier, plumed implies a feathered-and-decorative-feather quality, the visual register of Edwardian-and-Belle-Époque-plumed-hat hand-set-and-decorative ostrich-and-egret-feather Edwardian-and-Belle-Époque plumed-and-feathered-hat surfaces under Edwardian-and-Belle-Époque plumed-hat-and-feather millinery-light. Sits at the modifier-and-texture end of the grid, parallel to fluff and down in usage.

Indigofera tinctoria, the South Asian legume whose leaves yield the deep blue dye that has clothed humanity for at least four thousand years — Egyptian linen, Mayan textile, the slave-grown plantations of Carolina. The color refers to a freshly indigo-dyed cotton thread: a saturated, slightly violet-shifted deep blue with the slight lustre of a fiber surface oxidized in air. Deeper than cobalt, cooler than royal.