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

Shop it at 42 percent off in this indigo and gold option, or opt for denim in black or red with silver accents. —Caley Sturgill, Southern Living, 6 Feb. 2026

Raw indigo straight-leg jeans, slim tapered jeans with rip and repair details and wide-leg shorts with carpenter panels—offered in black and plum—are other denim highlights. —Angela Velasquez, Sourcing Journal, 6 Feb. 2026

Named for the three-point shaking technique pioneered by Japanese bartender Kazuo Uyeda, the lounge overlooks the Strip with indigo banquettes, a dark stone bar and floor-to-ceiling windows. —Melinda Sheckells, Forbes.com, 29 Jan. 2026

White is for summer, black is for winter, indigo is for dressing up, and a medium blue is for every day. —Kaelin Dodge, InStyle, 27 Jan. 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