Healthful Salve Sky

Old English hǣlth, health — adjectival suffix -ful. As a color modifier, healthful implies a clear-and-vital-and-wholesome quality where the hue carries the visual register of fresh-air-and-sunlight outdoor health-promoting environment. Sits at the crisp-and-wholesome end of the grid, parallel to salubrious and wholesome in usage.

Latin salve, hail-or-be-well. As a color modifier, salve implies a Latin-greeting-and-Salve-Regina-and-Roman-salute quality, the visual register of Salve-Regina-and-Pompeii-salve hand-Latin-greeting-and-Salve-Regina-and-Roman-salute Salve-Regina-and-Pompeii-salve-and-Roman-doormat-mosaic salve-and-Latin-greeting surfaces under Salve-Regina-and-Pompeii-salve-and-Roman-doormat-mosaic Pompeian-mosaic-and-Marian-antiphon Roman-greeting-light. Sits at the modifier-and-Latin end of the grid, parallel to ave and pax in usage.

The blue of a clear sky at noon — produced by Rayleigh scattering, the preferential dispersion of shorter wavelengths through atmospheric molecules. Air itself is colorless; the color we see is sunlight scattered toward our eyes by every cubic kilometer above. The reference shade is mid-latitude noon under a high pressure system: a clean, slightly green-shifted blue with the luminous depth of light scattered across an entire hemisphere of air.