Radiant Sour Goldenrod

From the Latin radiare, to emit rays — used as a color word since the seventeenth century for hues that read as luminous and emitting. Radiant gold, radiant pink: the implication is high luminance combined with the optical impression of an outward light. Sits in the bright-bucket center alongside glowing.

Old English sūr, acid-or-fermented. As a color modifier, sour implies a fermented-and-puckered-and-acid quality, the visual register of sourdough-and-Bavarian-sauerkraut-sour hand-fermented-and-puckered-and-acid sourdough-and-Bavarian-sauerkraut-sour-and-Belgian-Lambic sour-and-fermented-and-puckered surfaces under sourdough-and-Bavarian-sauerkraut-sour-and-Belgian-Lambic San-Francisco-sourdough-and-Brussels-Lambic fermented-puckered-light. Sits at the modifier-and-flavor end of the grid, parallel to tart and tang in usage.

Solidago, the late-summer wildflower of North American meadows whose tall sprays of small yellow flowers signal the end of the growing season. The color refers to the flower head at full bloom: a warm, slightly muted yellow-orange with the matte finish of small clustered florets. Cooler than mustard, deeper than dandelion. The state flower of Kentucky and Nebraska, a pollinator magnet, and the original native dye for early American homespun.