indigo

noun

in·​di·​go ˈin-di-ˌgō 

plural indigos or indigoes

1

: a deep reddish blue

2

: indigo plant

3

a

: a blue vat dye obtained from plants (such as indigo plants)

b

: the principal coloring matter C₁₆H₁₀N₂O₂ of natural indigo usually synthesized as a blue powder with a coppery luster

Examples of indigo in a Sentence

Recent Examples on the Web

This indigo patchwork style mixes rich blue hues with eye-catching patterns that can give a classic white sofa a whole new look. — Toni Sutton, PEOPLE, 6 Sep. 2026

The cabana-style restaurant—all white rattan, sea greens and artisanal ceramics—serves simple classics such as scorpion fish all’ acqua pazza and wave-fresh John Dory before the aquamarine and indigo tie-dye of the bay. — Condé Nast, Condé Nast Traveler, 3 Sep. 2026

The sky reminds Laurel less of Earth than of some gaseous planet, streams of indigo and violet and shocking pink, the setting sun layered between them. — ABC News, 31 Aug. 2026

Dyes such as indigo, for example, which colors your favorite blue jeans, are actually intended to fade and will do so throughout the life of the garment. — Madeline Buiano, Martha Stewart, 30 Aug. 2026

Word History

Etymology

Italian dialect, from Latin indicum, from Greek indikon, from neuter of indikos Indic, from Indos India

First Known Use

1555, in the meaning defined at sense 3a

Phrases Containing indigo

• indigo bunting
• indigo plant
• indigo snake
• wild indigo

Rhymes for indigo

• afterglow
• akimbo
• albino
• aliquot
• allegro
• amigo
• apropos
• audio
• bungalow
• calico
• calypso
• cameo

Kids Definition

indigo

noun

in·​di·​go ˈin-di-ˌgō 

plural indigos or indigoes

1

: a blue dye made artificially and formerly obtained from plants and especially indigo plants

2

: a deep reddish blue

Etymology

from an Italian dialect word indigo "a blue dye from indigo plants," from Latin indicum (same meaning), derived from Greek indikos (adjective) "of or relating to India"; so called because the plant dye was first widely produced in India

Medical Definition

indigo

noun

in·​di·​go ˈin-di-ˌgō 

plural indigos or indigoes

1

a

: a blue dye obtained from indigo plants (as Indigofera tinctoria of Africa and India, I. suffruticosa of South America, and I. arrecta of Arabia and Egypt)

b

: the principal coloring matter C₁₆H₁₀N₂O₂ of natural indigo usually synthesized as a blue powder with a coppery luster

called also indigotin

2

: indigo plant