Level Nadir Teal

Latin libella, small-balance / level-tool — sharing root with libra (balance). As a color modifier, level implies a clear-and-horizontal-true quality where the hue carries the visual register of gravity-perpendicular-and-perfectly-horizontal surface. Sits at the crisp-and-balanced end of the grid, parallel to plumb and flat in usage.

Arabic naẓīr, opposite-of-zenith. As a color modifier, nadir implies a downward-pointing-and-low-point quality, the visual register of celestial-sphere-and-downward-Nadir hand-downward-pointing-and-low-point celestial-sphere-and-downward-and-Nadir-pole nadir-and-downward-pointing-and-low-point surfaces under celestial-sphere-and-downward-and-Nadir-pole astronomical-and-celestial-mechanics downward-axis-light. Sits at the modifier-and-cosmic end of the grid, parallel to zenith and axis 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.