Open Thaw Lagoon

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 English thawian, to-melt-or-soften. As a color modifier, thaw implies a spring-melt-and-softening-frost quality, the visual register of English-spring-and-Pennine-thaw hand-spring-melt-and-softening-frost English-spring-and-Pennine-thaw-and-Cumbria-Highland-thaw thaw-and-spring-melt-and-softening-frost surfaces under English-spring-and-Pennine-thaw-and-Cumbria-Highland-thaw Yorkshire-Dales-and-Lake-District-and-Cairngorm spring-melt-light. Sits at the modifier-and-weather end of the grid, parallel to slush and rain in usage.

A shallow body of saltwater partially or fully enclosed by a barrier — coral atoll lagoons in the Pacific, Venice's Laguna Veneta, the Florida Keys' backcountry. The color refers to the average reflectance of a calm tropical lagoon at midday: a saturated, slightly muted blue-green with the optical clarity of shallow water over white sand. Brighter than reef, cooler than aquamarine, with the postcard weight of a Pacific atoll seen from above.