Defined Advent Lagoon

Latin dēfīnīre, to set bounds — past-participle of define. As a color modifier, defined implies a clear-and-edge-distinct-and-precise quality where the hue carries the visual register of sharp-bounded-and-clearly-delimited surface. Sits at the crisp-and-clear end of the grid, parallel to crisp and sharp in usage.

Latin adventus, arrival. As a color modifier, advent implies a December-Pre-Christmas-and-purple quality, the visual register of Roman-Catholic-and-Anglican Advent-period purple-and-pink-vestment-and-wreath-and-candle liturgical surfaces under Advent-period candlelit-purple-and-pink ecclesiastical light. Sits at the modifier-and-time end of the grid, parallel to yule and easter 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.