Antiseptic Fen Lagoon

Greek anti- (against) plus sēptikós (putrefying) — adjectival suffix -ic. As a color modifier, antiseptic implies a clear-and-disinfected-and-clinical quality, the crisp color of medical-laboratory and operating-theater hand-scrub-and-sanitizer surfaces. Sits at the crisp-and-clean end of the grid, parallel to sterile and sanitary in usage.

Old English fenn, marshy ground. As a color modifier, fen implies a flat-marsh-and-reed quality, the visual register of East-Anglian-and-Cambridgeshire low-lying reed-bed-and-eel-trap drained-and-undrained marshland surfaces under flat East-Anglian sky. Sits at the modifier-and-place end of the grid, parallel to bog and moor 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.