Definitions
1.nounA purplish-blue colour
2.nounAn indigo-colored dye obtained from certain plants (the indigo plant or woad), or a similar synthetic dye.
3.nounAn indigo plant, such as from species in genera Indigofera, Amorpha (false indigo), Baptisia (wild indigo), and Psorothamnus and Dalea (indigo bush).
4.adjectiveHaving a deep purplish-blue colour