Healthful Quad Peacock

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 quadrum, square. As a color modifier, quad implies an Oxford-and-Cambridge-college-quadrangle quality, the visual register of Oxford-and-Cambridge-college-quad hand-built four-sided-college-courtyard quad-and-cloister-and-lawn architectural surfaces under Oxford-and-Cambridge college-quadrangle academic light. Sits at the modifier-and-architecture end of the grid, parallel to court and atrium in usage.

Pavo cristatus, the Indian peafowl whose male displays the most elaborate sexual ornament in birds — a fan of two-meter eyespotted tail feathers in iridescent blue-green. The color is structural, not pigmented: created by interference patterns in the feather barbules. Peacock blue refers to the dominant body color: a saturated, slightly muted teal-blue with the optical depth of structural color. Cooler than persian, warmer than sapphire.