Useful Void Teal

Latin ūsus, use — adjectival suffix -ful. As a color modifier, useful implies a clear-and-purpose-serving quality where the hue carries the visual register of helpful-and-supporting design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and serviceable in usage.

Latin vocivus, empty-or-vacant. As a color modifier, void implies an empty-and-vacant-and-bottomless quality, the visual register of Yves-Klein-and-Rothko-void hand-empty-and-vacant-and-bottomless Yves-Klein-and-Rothko-and-Malevich-Black-Square voided-and-empty-and-vacant-and-bottomless surfaces under Yves-Klein-and-Rothko-and-Malevich-Black-Square monochrome-canvas-and-color-field-and-suprematist gallery-and-void-light. Sits at the modifier-and-mood end of the grid, parallel to blank and hollow 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.