from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. Any of various shrubs or herbs of the genus Indigofera in the pea family, having odd-pinnate leaves and usually red or purple flowers in axillary racemes.
  • n. A blue dye obtained from these plants or produced synthetically.
  • n. Any of several related plants, especially those of the genera Amorpha or Baptisia.
  • n. The hue of that portion of the visible spectrum lying between blue and violet, evoked in the human observer by radiant energy with wavelengths of approximately 420 to 450 nanometers; a dark blue to grayish purple blue.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A purplish-blue colour
  • n. An indigo-colored dye obtained from certain plants (the indigo plant or woad), or a similar synthetic dye.
  • adj. Having a deep blue colour.

from the GNU version of the Collaborative International Dictionary of English

  • adj. Having the color of, pertaining to, or derived from, indigo.
  • n. A kind of deep blue, one of the seven prismatic colors.
  • n. A blue dyestuff obtained from several plants belonging to very different genera and orders, such as, the woad, Isatis tinctoria (family Cruciferae), Indigofera suffroticosa, Indigofera tinctoria (family Leguminosae), Indigofera Anil, Nereum tinctorium, Polygonum tinctorium Ait. (family Polygonaceae), etc.; called also natural indigo. It is a dark blue earthy substance, tasteless and odorless, with a copper-violet luster when rubbed. Indigo does not exist in the plants as such, but is obtained by decomposition of the glycoside indican.

from The Century Dictionary and Cyclopedia

  • n. A substance obtained in the form of a blue powder from leguminous plants of the genus Indigofera, and used as a blue dye. See indigoplant.
  • n. The violet-blue color of the spectrum, extending, according to Helmholtz, from G two thirds of the way to F in the prismatic spectrum. The name was introduced by Newton, but has lately been discarded by the best writers.
  • n. An American leguminous plant, Baptisia australis. See Baptisia. Also called blue false indigo and wild indigo.
  • n. Same as Japanese indigo.
  • n. In Australia, any plant of the genus Swainsona of the bean family, especially S. galegifolia. See Swainsona.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a blue dye obtained from plants or made synthetically
  • n. a blue-violet color
  • adj. having a color between blue and violet
  • n. deciduous subshrub of southeastern Asia having pinnate leaves and clusters of red or purple flowers; a source of indigo dye


from The American Heritage® Dictionary of the English Language, 4th Edition

Spanish índigo and Dutch indigo (from Portuguese endego), both from Latin indicum, from Greek Indikon (pharmakon), Indian (dye), neuter of Indikos, of India, from India, India, from Indos, the Indus River, from Old Persian Hinduš, Sind; see Hindi.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Spanish indico, Portuguese indigo, or Dutch (via Portuguese) indigo, all from Latin indicum ("indigo"), from Ancient Greek Ἰνδικὸν ("Indian dye").



Log in or sign up to get involved in the conversation. It's quick and easy.

  • Interesting usage in a translated primary source from ca. 900 can be found in comment on perfumer.

    November 28, 2017

  • Past tense: indiwent.

    March 5, 2011

  • Did you hear about the cow who got into the blueberry patch?

    She mooed indigo.

    October 6, 2009