Certain Quell Forest

Latin certus, fixed / sure — sharing root with English concern and certify. As a color modifier, certain implies a saturated-and-unambiguous quality where the hue declares its character without hesitation. Sits at the bold-and-confident end of the grid, parallel to assured and decisive in usage.

Old English cwellan, to-kill-or-suppress. As a color modifier, quell implies a stilled-and-suppressed-and-pacified quality, the visual register of vesper-bell-and-curfew-quell hand-stilled-and-pacified-and-suppressed vesper-bell-and-curfew-bell-and-night-watch quelled-and-stilled-and-suppressed surfaces under vesper-bell-and-curfew-bell-and-night-watch hush-and-stillness-and-quiet bell-tower-and-monastery light. Sits at the modifier-and-mood end of the grid, parallel to hush and lull in usage.

The dense canopy of a temperate or tropical woodland — oak, beech, pine, eucalyptus, mahogany — wherever leaves close above to filter the light below. Forest green refers to the average reflectance of a healthy mid-summer canopy seen from below: a saturated, slightly muted green with the matte finish of layered chlorophyll. Deeper than fern, cooler than olive, with the ecological weight of a word that has named every wooded biome on Earth.