Azure
The heraldic name for blue; in general use, the clear blue of a cloudless sky.
Also: blue (heraldry), sky blue
Azure reached European languages through Arabic from the Persian name for lapis lazuli, the blue stone. In heraldry it means blue of any clear shade, shown in line drawings by horizontal lines. The blue field with gold lilies of the old French royal arms is the best-known example. Outside heraldry, azure is a poetic word for the colour of the sky, and on colour wheels for screens it names the hue halfway between blue and cyan. Words for blue in Spanish, Portuguese and Italian share the same root.