The Japanese language has separate words for the colors blue and green. In modern Japanese, the word for blue is “ao” (青) and the word for green is “midori” (緑). However, this has not always been the case historically. Ancient Japanese did not make a distinction between blue and green and used the word “ao” to refer to both colors.
The History of “Ao” Meaning Blue and Green
In ancient Japanese, the word “ao” was used to describe both blue and green shades. This is similar to some other languages like Korean that use a single word to refer to what English speakers consider blue and green. The first recorded uses of “ao” date back to the 8th century in Japan’s oldest surviving chronicle, the “Kojiki.” It is believed that the word originally referred to the color of foliage and lush vegetation. Over time, it came to be used for other green and blue objects like the sky and water.
This lack of distinction between blue and green is not unique to Japanese. It is found in many ancient languages and cultures. Some linguists believe this is because blue is rare in nature while green is common. Early humans did not have a great need to distinguish between the two colors. Another theory is that blue and green appear similar in natural lightings so were not perceived as very different. Ancient Japanese poetry also used “ao” in broad symbolic ways to refer to things far away, depth, and the mystical.
By the Heian period in the 8th to 12th centuries CE, the Japanese language started using separate words for green (“midori”) and blue (“ao”). But the process was gradual. For some time, “ao” was still used for shades of green alongside the newer term “midori.” By the Muromachi period in the 14th to 16th centuries, the transition was complete and “ao” referred exclusively to blue while “midori” was used for green.
Reasons for the Shift in Definition
There are several theories as to why the original broad meaning of “ao” narrowed over time to refer specifically to blue:
- Increased trade and contact with China introduced more words like “midori” for green while “ao” retargeted to blue.
- The growth of dyeing technology led to greater variety in colored clothing, leading people to distinguish blue and green.
- Philosophical and religious influence from China emphasized the symbolic importance of the five elements (metal, wood, water, fire, earth). Blue and green represented different elements.
- The advent of colored art and painting motivated distinguishing blue and green visually for pigments and dyes.
The diagrams below summarize the timeline and factors that led ancient Japanese “ao” referring broadly to blue and green evolve into separate modern words:
| Time Period | Use of “Ao” | Reasons for Change |
|---|---|---|
| Ancient Japanese (before 5th century CE) | Refers to blue, green, and other colors | Limited color vocabulary in nature |
| Heian Period (794-1185 CE) | Still used for blue and green but “midori” emerges for green | Chinese and Buddhist influence introduces new color terms |
| Muromachi Period (1336-1573 CE) | “Ao” refers exclusively to blue | Advances in dyeing and painting require color precision |
This change in the Japanese language exemplifies how cultures evolve new color vocabularies in response to cultural, technological, and environmental influences over time. The emergence of “midori” for green and the retention of “ao” for only blue occurred due to both outside word borrowing and internal pressures to describe colors more precisely.
Examples of “Ao” Usage for Blue and Green
Here are some examples of how the kanji 青 is read as “ao” in Japanese words referring specifically to blue and green shades today:
Blue Ao
- Aoi (青い) – blue
- Aomuke (青焼け) – sunburn, tan
- Aozora (青空) – blue sky
- Seijin (青筋) – blue vein
Green Ao
- Aomidori (青緑) – blue green
- Aokusari (青臭) – green smell (like chlorophyll)
- Aoyagi (青柳) – green willow
- Aobana (青花) – green flower
There are also many common Japanese words with the “ao” kanji that refer to things associated with green and blue:
- Seito (青糖) – blue/green algae
- Daiao (大青) – large bluefin tuna
- Aoko (青木) – name meaning “green tree”
So while originally covering a wide span of green and blue hues, the meaning of “ao” has transformed over centuries to refer specifically to blue in modern Japanese while “midori” is used for green. But you can still see its ancient roots in words associated with green landscapes, vegetation, and herbs.
Use of the Word “Blue” in English
The evolution of “ao” from a broad term for blue and green to one meaning specifically blue is mirrored in the English word “blue.” In Old English, the word “blæw” referred to a range of colors from blue to green to black. It comes from the Proto-Germanic “blæwaz” and is related to the Latin word “flavus” meaning yellow.
Like “ao,” “blue” in its early Germanic roots does not seem to have denoted a precise color term but rather described darker or desaturated shades across blue, green, and grey. As dyeing and painting techniques developed in medieval Europe, the application of “blue” narrowed to its modern usage for azure and related shades.
Other languages like Russian, Italian, and Arabic also have words for blue that previously encompassed blue, grey, and green colors before their meanings simplified. The path of “ao” and “blue” mirror a common linguistic evolution as civilizations progress from simple, broad color vocabularies to more sophisticated and precise terms for shades of the spectrum.
Conclusion
The Japanese word “ao” has an intriguing history shifting from an ancient term for blue and green to a modern word meaning specifically blue. Analyzing this evolution provides insights into how color vocabularies change over time based on cultural exposure, technological changes, and linguistic needs. The narrowing of “ao” parallels similar developments in languages around the world like “blue” in English. Tracing these words offers a window into the interconnected progression of culture and language.