indigo

American  

[in-di-goh] / ˈɪn dɪˌgoʊ /

noun

• indigos,
  plural
• indigoes
  plural

1. a blue dye obtained from various plants, especially of the genus Indigofera, or manufactured synthetically.

2. indigo blue.

3. any of numerous hairy plants belonging to the genus Indigofera, of the legume family, having pinnate leaves and clusters of usually red or purple flowers.

4. a color ranging from a deep violet blue to a dark, grayish blue.

---

adjective

1. Also called indigotic.  Also called indigo-blue,.  of the color indigo.

indigo British  

/ ˈɪndɪˌɡəʊ /

noun

1. Also called: indigotin.  a blue vat dye originally obtained from plants but now made synthetically

2. any of various tropical plants of the leguminous genus Indigofera, such as the anil, that yield this dye Compare wild indigo

3. 1. any of a group of colours that have the same blue-violet hue; a spectral colour

   2. ( as adjective )

      an indigo carpet

---

Other Word Forms

Derived Forms

• indigotic
  adjective

Inflected Forms

Nouns

• indigoes
  plural
• indigos
  plural

Etymology

Origin of indigo

1545–55; < Spanish or Portuguese, variant of índico < Latin indicum < Greek indikón, noun use of neuter of Indikós Indic

Explanation

Indigo is a flowering plant that's native to Asia, and it's also the name of a deep blue dye made from the leaves of the indigo plant. You can also use the word to mean the shade of blue itself. The indigo plant is in the pea family. While this plant often has brightly colored flowers, indigo dye is traditionally made from the plant's leaves. This type of tint was once the most common natural dye in the world — though today, most of what's called indigo is synthetically made. Indigo is also one of the colors of the rainbow: red, orange, yellow, green, blue, indigo, and violet. The Greek root indikon means "blue dye from India."

Example Sentences

See Examples For:

indigo indigoes indigos

The study examined indigo light, a short wavelength of visible light that is plentiful in natural sunlight but largely absent from standard white LED lighting.

From Science Daily ● Aug. 26, 2026

The reverse side of the Sydney Marathon medal shows a gold and indigo pattern designed by First Nations artist Ambrose Killian, widely commended for its ornate pattern.

From BBC ● Aug. 23, 2026

The orange glow from my Nesso lamp lit his face while the indigo sky pressed against the window behind him.

From Los Angeles Times ● Apr. 24, 2026

As the sub dropped below 200 metres, the last traces of light disappeared, and indigo faded into total darkness.

From Barron's ● Jan. 26, 2026

We arose in the dark, hours before sunrise, when there was barely a smudge of indigo along the eastern sky and the rest of the horizon was still pure pitch.

From "The Evolution of Calpurnia Tate" by Jacqueline Kelly

Amorpha, a-mor′fa, n. a genus of North American shrubs of the bean family, the false indigoes or lead-plants—also bastard or wild indigo.

From Chambers's Twentieth Century Dictionary (part 1 of 4: A-D) by Various

Strangely enough, in the vicinity of Denver in 1901, these birds were abundant and as easily approached and studied as are the indigoes of the East.

From Birds of the Rockies by Leander S. (Leander Sylvester) Keyser

The way I feel lately sometimes, honest, I think if I get to getting the indigoes much deeper, there's no telling where they'll land me.

From Every Soul Hath Its Song by Fannie Hurst

The sky, low and heavy with tumbled cloud, was a study in greys and indigoes; the earth a still, uncharted waste.

From The Great Amulet by Maud Diver

Jim's idea of the word "indigoes" was, that it drew its meaning partly from the color of the articles designated, and partly from their office.

From Sevenoaks by J. G. (Josiah Gilbert) Holland

Her paintings, in black-on-black or leavened by indigos or grays, include sharp lines reminiscent of architectural drawings, but also effusive layers and drips.

From New York Times ● Nov. 10, 2022

At the mixing station, Andrea Arriola-Pinto swirled light magentas, indigos and dark purples in four separate dishes like an artist mixing paint.

From Los Angeles Times ● Jun. 14, 2022

On São Tomé and Príncipe, two tiny islands off the west coast of Africa, Rayna Bell came across Lilliputian frogs, decked out in lime green, speckled in leopard print and daubed with indigos.

From Nature ● Oct. 6, 2015

Hallway carpets with comically giant indigos and carrot-orange walls conspire to create a visual jungle.

From New York Times ● Jun. 18, 2010

The moon paints the sky in deep violets and indigos.

From "The Belles" by Dhonielle Clayton

Related Words

• blue-green