indigo

plural indigos · plural indigoes

1. countableuncountableA purplish-blue color.
2. countableuncountableA greenish dark blue color; the color of indigo dye.

   The night was considerably clearer than anybody on board her desired when the schooner Ventura headed for the land. It rose in places, black and sharp against the velvety indigo, over her dipping bow, though most of the low littoral was wrapped in obscurity.

   1907 January, Harold Bindloss, chapter 6, in The Dust of Conflict, 1st Canadian edition, Toronto, Ont.: McLeod & Allen, →OCLC

3. countableuncountableA blue-colored dye obtained from certain plants (indigo plant or woad), or a similar synthetic dye.
4. countableuncountableAn indigo plant, such as from species in genera Indigofera, Amorpha (false indigo), Baptisia (wild indigo), and Psorothamnus and Dalea (indigo bush).

   A Southern planter has been sowing indigo and cotton together. Perhaps he contemplates raising blue cotton; and should he wa­ter the plants with nitric acid, he would probably raise gun cotton—if any.

   1846, editorial staff, “Growing Cotton”, in Scientific American, series 1, Volume 2, Issue 13, page 98

comparative more indigo · superlative most indigo

1. having a deep purplish-blue colour

1. A local government area in north-east Victoria, Australia, named after Indigo Valley; in full, the Shire of Indigo.
2. A female given name.

   Details of Thunberg’s charge came as Just Stop Oil said its cofounders, Indigo Rumbelow and Roger Hallam, were arrested on Wednesday morning following dawn raids at their homes.

   2023 October 18, Damien Gayle, “Greta Thunberg charged with public order offence after London oil protest”, in The Guardian