azure

Azure comes from Middle English asure, borrowed from Old French azur, which traces to Arabic lāzaward, meaning lapis lazuli. That Arabic word came from Classical Persian lājward, named for the region of Lajward in Badakhshan, where the stone was mined.

The word passed from a place name for a mineral source into a word for the stone itself, then into French and English as a name for its deep blue color.

The Old French azur lost its initial 'l' along the way, as speakers mistook it for the French article l' — a small mishearing that reshaped the word. Italian azzurro and Spanish azul are cousins that kept closer to the original sound.