In many languages, the colors described in English as "blue" and "green" are colexified, i.e., expressed using a single umbrella term. To render this ambiguous notion in English, linguists use the blend word grue, from green and blue, a term coined by the philosopher Nelson Goodmanwith an unrelated meaningin his 1955 Fact, Fiction, and Forecast to illustrate his "new riddle of induction".

The exact definition of "blue" and "green" may be complicated by the speakers not primarily distinguishing the hue, but using terms that describe other color components such as saturation and luminosity, or other properties of the object being described. For example, "blue" and "green" might be distinguished, but a single term might be used for both if the color is dark. Furthermore, green might be associated with yellow, and blue with either black or gray.

According to Brent Berlin and Paul Kay's 1969 study Basic Color Terms: Their Universality and Evolution, distinct terms for brown, purple, pink, orange, and gray will not emerge in a language until the language has made a distinction between green and blue. In their account of the development of color terms the first terms to emerge are those for white/black (or light/dark), red/blue and green/yellow.

Afro-Asiatic Amazigh The word for blue in the Amazigh (Berber) language is . In some dialects of Amazigh, like Shilha or Kabyle, the word is used for both green and blue.

Arabic The color of the sky is sometimes referred to as "the green" in some dialects of Classical Arabic poetry, in which it is (). In Arabic the word for blue is (). The Arabic word for green is ().

In Moroccan Arabic, the word for light blue is , whereas () stands for blue and () for green. The word () is used to describe the color of a suffocated person, and is also used pejoratively as a synonym to "dumb, stupid".

Egyptian The ancient Egyptian word wadjet covered the range of blue, blue-green, and green. It was the name of a goddess, the patroness of Lower Egypt, represented as a cobra called Wadjet, "the green one", or as the Eye of Horus, also called by the same name. At the same time, wedjet was the word used for Egyptian blue in faience ceramics.

Hebrew In Hebrew, the word () means blue, while () means green and has the same root, (j-r-q), as the word for "vegetables" (, ). However, in classical Hebrew, can mean both green and yellow, giving rise to such expressions as 'leek green' (Tiberian Hebrew ) to specify green to the exclusion of yellow. Like Russian and Italian, Hebrew has a separate name for light blue (, )—the color of the sky and of tzitzit on the tallit, a ritual garment. This color has special symbolic significance in both Judaism and Jewish culture.

American languages Chahta The Choctaw language has two words, and , which have different meanings depending on the source. In 1852 was translated variously as 'pale blue' or 'pale green', is given as swarthy, and is defined as 'deep blue', 'gray', 'green', or 'sky blue'. In 1880, and are both given as blue, and green is not specifically listed as a color. In an 1892 dictionary, is deep blue or green, is pale blue or bright green, and a third word is 'bright green' (resembling a , a species of parrot). By 1915, the authoritative Byington dictionary gives as blue and as green, blue, gray, verdant. A coursebook from 2001 differentiates based on brightness, giving as 'bright blue/green' and as 'pale or dull blue/green'. Modern usage in the Choctaw Nation of Oklahoma language school is to use for 'blue' and for 'green', with no distinction for brightness.

Kanienʼkéha The language of the Kanien'kehá:ka Nation at Akwesasne is at Stage VII on the Berlin–Kay Scale, and possesses distinct terms for a broad range of spectral and nonspectral colors such as , , , , and . According to one researcher, the Kanien'kehá:ka term for purple is , which translates to , a recent, post-Christianization coinage. The way in which purple was categorized and referenced prior to the addition of the latter term is not clear.

Lakota In the Lakota language, the word is used for both blue and green, though the word (a mixture of the words , and ) has become common ( can also be used). This is in line with common practice of using for orange ( meaning ), and for .

Mapudungun Mapudungun, spoken by indigenous peoples of Chile and Argentina, distinguishes between , and . The word was formerly used to refer to a sky blue, and also refers to the bluish color of stones.

Mayan Single words for blue/green are also found in Mayan languages; for example, in the Yucatec Maya language, is .

Tupian Tupian languages did not originally differ between the two colors, though they may now as a result of interference of Spanish (in the case of Guaraní) or Portuguese (in the case of Nheengatu). The Tupi word meant both, as does the Guaraní . In modern Tupi (Nheengatu) the word can be used for green and for blue. However, also means immature, as in , and can also mean blue. In modern Guarani, the word is used for blue and (which literally means "dark green/blue") is used for green. The word , which is cognate with Nheengatu , also means .

Austronesian languages Filipino (Tagalog) Speakers of Tagalog most commonly use the Spanish loanwords for blue and green— (from Spanish ) and (from Spanish ), respectively. Although these words are much more common in spoken use, Tagalog has native terms: for blue and for green, which are seen as archaic and more flowery. These are mostly confined to formal and academic writings, alongside artistic fields such literature, music, and poetry.

In Cebuano, another major Philippine language, the native words for "blue" and "green" end in the same syllable: and , respectively. means sky blue, while is fresh leaf green (i.e., neither brownish nor yellowish).

Humor and jokes of a sexual or derogatory nature that would otherwise be described as "blue" in English (e.g., "blue comedy", "blue joke") are called "green" in Philippine English. This is a calque of the Hispanic term .

Javanese Modern Javanese has distinct words for blue and green . These words are derived from Old Javanese and . However, in Old Javanese could mean pale blue, grayish blue, greenish blue, or even turquoise, while which means green, could also mean the blue-green color of clear water. This concept of as 'grue' can also be seen in the neighboring language of Madurese, where means both 'blue' and 'green'. In contemporary use, the word 'green' can be distinguished from by using the term 'leaf grue'. and in Modern Javanese are cognates of Malay/Indonesian and which both have the same meaning.

Māori Māori spoken before contact with Europeans did not distinguish between blue and green, using the word namu (e.g. in pounamu) for both, while words describing greenery in vegetation (e.g. ota, mata) or birds (kākāriki) were dominant in 19th century dictionaries. Descriptions of the new Anglocentric "blue" was developed in association with the sky (rangi; e.g. kikorangi and kahurangi), while darker hues are perceived closer to black like pako (variant of pango) and uriuri.

Dravidian Kannada The Kannada language distinguishes between blue ( ), green ( ) and yellow ( ). The prefix () would indicate darker colors while the prefix () would indicate light colors. Thus () would mean dark/deep blue, while () would mean light blue.

Tamil The Tamil language distinguishes between the colors , , and . The prefix would indicate dark colors while the prefix would indicate light colors. Thus, would be dark green while would be light green.

Telugu The Telugu language uses a single word, , for green and yellow. To differentiate between the two shades, another word is prefixed in some cases. For example, green will be called and yellow .

Malayalam In Malayalam, there are distinct words for blue ( ), green ( ) and yellow ( ).

East Asian languages Chinese

The modern Standard Chinese language has the blue–green distinction ( for blue and for green); however, another word that predates the modern vernacular, (),Bogushevskaya, V. (2015) “GRUE in Chinese”. In is also used in many contexts. The character depicts the budding of a young plant and it could be understood as "verdant", but the word is used to describe colors ranging from light and yellowish green through deep blue all the way to black, as in For example, the flag of the Republic of China is referred to as (, ) whereas is the Chinese word for "green vegetable", referring to bok choy, and the opposing sides of the game liubo were known as and white in antiquityThe manuscript Rules of Liubo discovered 2011 in the tomb of the Marquis of Haihun in Jiangxi. despite using black and white pieces. was the traditional designation of both blue and green for much of the history of the Chinese language, while originally referred to the dye of the indigo plant.The defines as 'grass for dye': However, as a particular 'shade' of applied to cloth and clothingThe defines as 'cloth of yellowish color': has been attested since the Book of Odes (1000600BC), as in the title of Ode 27 "Green Upper Garment") in the Airs of Bei section. After the discarding of Classical Chinese in favor of modern vernacular Chinese, the modern terms for blue and green are now more commonly used than as standalone color terms, although is still part of many common noun phrases. The two forms can also be encountered combined as and , with being used as an intensifier. In modern scientific contexts, refers to cyan as a narrow range of color in between blue and green, and the modern color names are used when referring to other shades of blue or of green.

Japanese + Traditional colors of Japan#5B8930 , listed with yellow#6B9362 , listed with blue

The Japanese words and , the same kanji character as the Chinese , can refer to either blue or green depending on the situation. Modern Japanese has a word for , but it is a relatively recent usage. Ancient Japanese did not have this distinction: the word came into use only in the Heian period and, at that time and for a long time thereafter, was still considered a shade of . Educational materials distinguishing green and blue came into use only after World War II; thus, even though most Japanese consider them to be green, the word is still used to describe certain vegetables, apples, and vegetation. is also the word used to refer to the color on a traffic light that signals drivers to "go". However, most other objects—a green car, a green sweater, etc.—will generally be called . Japanese people also sometimes use the word , based on the English word "green", for colors. The language also has several other words meaning specific shades of green and blue.

Korean The native Korean word () can refer to either blue or green depending on the situation. It is used for blue as in ( ), or for green as in ( ), ( ). () is a noun-modifying form. Another word () explicitly refers to blue, but it exceptionally means green in ( ). Sino-Korean expressions / ( adj./n.) or / ( n.) refers to green, but it is a relatively recent usage.

Mongolian Modern Mongolian makes a distinction between green (, ) and blue, which has separate categories for light blue (, ) and dark blue (, ). Historically, Mongolian included greens such as fresh grass in the category, and became a more common term in the modern era.

Tibetan In Tibetan, (Wylie ) is the term traditionally given for the color of the sky and of grass.Yisun Zhang. "Bod rgya tshig mdzod chen mo". University of Virginia: Mi rigs dpe skrun khaṅ. (1993: 718) This term also falls into the general pattern of naming colors by appending the suffix , as in , , , and . Conspicuously, the term for is , likely related to , and defined as—"the grue (sngon po) sprout of wheat or barley".Yisun Zhang. "Bod rgya tshig mdzod chen mo". University of Virginia: Mi rigs dpe skrun khaṅ. (1993: 921)

Vietnamese