means A deep blue-violet color sitting between blue and violet, and the plant-derived dye that originally produced it.

from From Latin 'indicum,' meaning 'from India,' the source of the dye in the ancient Mediterranean world — itself from Greek 'indikon.' The trail leads back to the Indus river region, the same root that gave us the name 'India' itself. So the color is, quite literally, named for a place: a bottle of 'India,' poured into the spectrum.