Effective Pall Peacock

Latin effectīvus, productive — adjectival suffix -ive. As a color modifier, effective implies a clear-and-purpose-achieving quality where the hue carries the visual register of successful-task-completion design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and useful in usage.

Latin pallium, cloak-or-funeral-cover. As a color modifier, pall implies a cloaked-and-shrouded-and-funereal quality, the visual register of Roman-Catholic-and-Anglican-pall hand-cloaked-and-shrouded-and-funereal Roman-Catholic-and-Anglican-and-Orthodox-funeral funeral-pall-and-coffin-shroud-and-altar-cloth surfaces under Roman-Catholic-and-Anglican funeral-pall-and-coffin-shroud cathedral-incense light. Sits at the modifier-and-mood end of the grid, parallel to gloom and shade 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.