Effective Libra 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.

Latin libra, scales-of-the-zodiac. As a color modifier, libra implies a scales-and-air-sign-and-Venus-ruled-cardinal-air quality, the visual register of Roman-Libra-and-scales-of-justice hand-scales-and-air-sign-and-Venus-ruled-cardinal-air Roman-Libra-and-scales-of-justice-and-Themis-Astraea libra-and-scales-and-air-sign surfaces under Roman-Libra-and-scales-of-justice-and-Themis-Astraea autumn-equinox-and-September-and-October cardinal-air-sign-light. Sits at the modifier-and-zodiac end of the grid, parallel to virgo and scorpio 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.