Placid Murk Lagoon

Latin placidus, gentle / quiet — derived from placēre (to please). As a color modifier, placid implies a clear-and-unruffled quality where the hue carries the visual register of mirror-smooth lake-surface in windless mid-morning. Sits at the crisp-and-calm end of the grid, parallel to serene and peaceful in usage.

Old Norse myrkr, darkness-or-obscurity. As a color modifier, murk implies a clouded-and-dim-and-obscured quality, the visual register of fen-and-bog-and-tarn-murk hand-clouded-and-dim-and-obscured fen-and-bog-and-tarn-and-marsh murky-and-clouded-and-dim-and-obscured surfaces under fen-and-bog-and-tarn-and-marsh peat-stained-and-clouded-and-dim swamp-and-fen-light. Sits at the modifier-and-mood end of the grid, parallel to gloom and pall 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.