Open Frock Teal

Old English open, unobstructed — used as a color modifier since the eighteenth century for hues that read as airy or uncrowded. Open blue, open green: moderate saturation combined with optical spaciousness, the slight visual breath of a hue that doesn't crowd the surface it covers. Sits at the crisp-bucket center alongside clear.

Old French froc, monk's-habit-or-loose-garment. As a color modifier, frock implies a monk's-habit-and-pinafore-and-day-frock quality, the visual register of Benedictine-monk's-frock-and-Edwardian-day-frock hand-monk's-habit-and-pinafore-and-day-frock Benedictine-monk's-frock-and-Edwardian-day-frock-and-pinafore frock-and-monk's-habit-and-pinafore surfaces under Benedictine-monk's-frock-and-Edwardian-day-frock-and-pinafore Cluny-Abbey-and-Edwardian-tea-room habit-and-day-dress-light. Sits at the modifier-and-textile end of the grid, parallel to gown and cope 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.