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Outside/Inbox: What is the etymology of the color blue? Is it the same across cultures?

An Aztec heritage dancer wears traditional regalia during the Latino Heritage Festival in Des Moines, Iowa Sept. 26, 2015.
DoD News photo by EJ Hersom (public domain)
An Aztec heritage dancer wears traditional regalia during the Latino Heritage Festival in Des Moines, Iowa Sept. 26, 2015.

Every other Friday on Morning Edition, the Outside/In team answers a question from a listener about the natural world. For the past few weeks, we’ve been tackling queries on the theme of “blue.”

Calvin, in Des Moines, Iowa, sent us this message:

“I’m interested in the etymology. What is the history of the word ‘blue’? And is the idea of the color consistent throughout history, and in different cultures? Like, is our blue the same as what the Aztecs would say the color blue is? Thanks. Love the pod!” 

Blue by any other name

What I love most about etymology-related questions is also what makes them so hard to answer: Language is incredibly fluid, and there are rarely tidy origins for a particular word or phrase.

That being said, the English word “blue” is Germanic in origin, and has roots in Old French and Old Norse. Some of the various words it originates from translate to things like “sky-colored,” or “lead-colored” (and yes, lead can have a bluish tint).

This goes to show you that historically humans have often tied colors to familiar objects, which can make for some linguistic color-mixing. Consider a bruise – which can be blue, black or yellow. Another good example is water. A lot of Indo-European languages have root words describing the color of the sea that could be used to describe green, blue, and gray.

Kai Kupferschmidt is a science journalist and author of “Blue: In Search of Nature’s Rarest Color.”

“In fact, there’s still quite a few languages in the world where green and blue are the same word - where there’s just one word for those two colors.”

In our last Outside/Inbox, Kupferschmidt explained that the color blue is relatively rare in nature,and says that may be why it’s typically also the last major color to get its own name.

“There's different arguments to why that might be,” Kai said, “but one argument has been that you really only need a word for a color once you're able to separate that color from an object.”

In other words, it’s hard to give a color a name until you turn it into a pigment and dye something new with it.

Lapis lazuli.
James E. Petts (CC BY 2.0)
Lapis lazuli.

Out of the blue and into the indigo

Calvin also asked if the color blue is consistent across cultures. Whether you’re talking about the actual color, our perception of it, or even the associations it conjures, the answer is a pretty resounding no.

In Mayan and Aztec cultures, blue pigment was derived from a plant commonly known today as Guatemalan Indigo. That pigment is quite different from the ultramarine derived from lapis lazuli, a stone mined in Afghanistan that was historically used in Asian and European cultures.

As for language, our wide and contradictory use of blue in a variety of idioms reveals its fickle nature. The color blue is used to signify royalty, but is also associated with “blue-collar” workers. Baby blue might be considered a color of innocence or loyalty, but “blue movies” are obscene or pornographic.

The comedian Hannah Gadsby has a good standup bit about these contradictions.

“If you’re feeling blue, you’re sad,” she says, “but optimism? Blue skies ahead! A blueprint is a plan, but if something happens that’s not on the plan, where does that come from? Out of the blue!”

Again, Kupferschmidt thinks our broad associations with the color blue might have to do with its relative rarity in nature.

“I think it's partly because blue doesn't have these very fixed objects attached to it, like say, red and blood. I think it's kind of more open to different associations.”

Ultimately, we can’t even say that a color is consistent from person to person if we’re looking at the exact same thing. Not everybody has all three color-perceiving cones, and there are even variations in visual acuity between the folks that do.

So the wavelengths of light may be the same, but how we perceive it is a question of cultural conditioning and biology. Isn’t that neat?

Submit your question about the natural world If you’d like to submit a question to the Outside/In team, you can record it as a voice memo on your smartphone and send it to You can also leave a message on our hotline, 1-844-GO-OTTER.

Outside/In is a podcast! Subscribe wherever you get yours.

Outside/In is a show where curiosity and the natural world collide. Click here for podcast episodes and more.
Taylor Quimby is Supervising Senior Producer of the environmental podcast Outside/In, Producer/Reporter/Host of Patient Zero, and Senior Producer of the serialized true crime podcast Bear Brook.

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