Effective Wold Teal

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.

Old English wald, forested upland. As a color modifier, wold implies a chalk-upland-and-grass quality, the visual register of Lincolnshire-and-Yorkshire-Wolds chalk-and-limestone open-upland sheep-pasture-and-arable rolling surfaces under big-sky Lincolnshire-Wolds open-country light. Sits at the modifier-and-place end of the grid, parallel to moor and heath in usage.

Anas crecca, the small dabbling duck whose male in breeding plumage sports a chestnut head crossed by a glossy green-blue stripe. The color refers to that stripe — the iridescent panel just behind the eye: a saturated, slightly muted blue-green with the optical depth of structural color rather than pigment. Cooler than cypress, warmer than cerulean, with the ornithological specificity of a color named for one feather of one bird.