Where does “cyan” come from?

Cyan comes from Ancient Greek κύανος, derived from Proto-Indo-European ḱʷei-, itself a variant of Proto-Indo-European ḱwey-.

cyan (English): A vibrant pale greenish-blue colour between blue...

Definitions

Step	Language	Word	Meaning
1	Ancient Greek	κύανος	blue
2	Hittite	kuwannan-	precious stone, copper, blue
3	Proto-Indo-European	ḱwey-	to hiss, to whistle, to whisper; to shine, white,...

cyan — Etymology, Origin & Word History | Etymology Explorer