Usage of indigo?

it was a plant that produced blue die

Usually, an indigo is indicated as a child or person that has different understanding about life, spirit, and the world around them. He or she feel that way from the bottom of his or her thought,...

Between blua and violet in the rainbow

custom (an accepted or habitual practice)

Indigo is a deep blue purple color. It is also the name of a dye that is derived from the indigo plant.