bright, splendid, glorious
凞 centers on radiant light and splendor: something bright, glorious, and visually magnificent.
凞 is a rare character combining 冫 (ice) with 熈, which itself relates to brightness or fire. The exact historical development is uncertain, but it likely expresses a sense of brilliant light or glory.
The ice radical 冫 beside 熈 (a shape associated with fire and brightness) creates a striking contrast: imagine ice reflecting a glorious, splendid light.
For キ, picture a bright, glorious key unlocking a treasure chest: key -> キ, and the key shines with splendor.