In literature, "indigo" is a multifaceted term that transcends its identity as merely a color. In works with a socio-political focus, such as in a well-known colonial drama, it emerges as a symbol of economic exploitation and labor, representing both the crop itself and its heavy burden on agrarian communities ([1], [2], [3]). Meanwhile, in adventure narratives and descriptive accounts, the word paints vivid scenes—whether evoking the mysterious depths of an "indigo sea" or lending a rich hue to fabrics and skies ([4], [5], [6]). Scientific and technical texts also employ the term to define a precise point in the visible spectrum, underscoring its cultural and aesthetic resonance ([7], [8]).
- Saheb , have not insects attacked thine Indigo-twigs?
— from Nil Darpan; or, The Indigo Planting Mirror, A Drama. by Dinabandhu Mitra
- We have nearly abandoned all the ploughs; still we have to cultivate Indigo.
— from Nil Darpan; or, The Indigo Planting Mirror, A Drama. by Dinabandhu Mitra
- Immediately, one whispered to the other, “The Indigo giant, the Indigo giant.”
— from Nil Darpan; or, The Indigo Planting Mirror, A Drama. by Dinabandhu Mitra
- “Where?” “Do you see that island?” continued the captain, pointing to a conical pile rising from the indigo sea.
— from The Count of Monte Cristo by Alexandre Dumas and Auguste Maquet
- Murky as well, and very rich in saline material, their pure indigo contrasts with the green waves surrounding them.
— from Twenty Thousand Leagues Under the Seas: An Underwater Tour of the World by Jules Verne
- The sea, absorbing every color of the prism except its blue rays, reflected the latter in every direction and sported a wonderful indigo tint.
— from Twenty Thousand Leagues Under the Seas: An Underwater Tour of the World by Jules Verne
- At Q where the violet-making and indigo-making Rays are mixed, it must be a violet inclining much to indigo.
— from Opticks : by Isaac Newton
- And so the Colours in order from P to τ ought to be violet, indigo, blue, very faint green, white, faint yellow, orange, red.
— from Opticks : by Isaac Newton