What is the etymology of word "chromatic" (= relating to color) in music?

Question

Regarding "chromatic," I found on Wiktionary:

Latin chrōmaticus, from Ancient Greek χρωματικός (khrōmatikós, “relating to colour; one of the three types of tetrachord in Greek music”)

Then I traced it to Greek genera:

In the chromatic tetrachord the second string of the lyre was lowered from G to G♭, so that the two lower intervals in the tetrachord were semitones, making the pitches A G♭ F E.

And to Genus (music), Etymology, which describes the etymolohy of diatonic, but not chromatic.

So my question remains: Why was the word chromatic ("relating to color") linked to the above tetrachord in Ancient Greece?

Answer 1

Why was the word chromatic ("relating to color") linked to the above tetrachord in Ancient Greece?

As mentioned in comments this is probably a bit off-topic, but Liddell and Scott, the standard dictionary of Ancient Greek, offers this in its entry for chroma:

(I. to III. are various meanings to do with colour, hue, pigment)

IV. complexion, character of style in writing

...

3. in Music, a modification of the simplest music, but esp[ecially] b. chromatic scale or music, “οὔτε χρῶμα δειλοὺς οὔτε ἁρμονία ἀνδρείους ποιεῖ” ["neither the color of cowards nor the harmony of brave poets", says google translate] Anon. in PHib.1.13.22

So maybe it's as simple as: this music was seen as 'colourful' by comparison to other music.

Answer 2

This is only a half answer to give additional context to the use of the word "chromatic":

The earliest reference to "chromatic" that I know of appears when later theorists like Aristoxenus and Ptolemy reference Archytas (ca. 400 BC) and his discussion of the diatonic, chromatic, and enharmonic genera (the plural form of "genus").

Archytas referred to the genera as

the diatonic ("through the tones"), the chromatic ("through the colors" or "shades"), and the enharmonic ("through proper attunement"). (from Barker 1989, Greek Musical Writings)

So it seems clear that the etymology was directly related to color and shading as compared to the diatonic genus, and it appeared several centuries earlier than most think.

Note that these terms and meanings are continuously found in treatises (like those of Boethius, 6th century) that found their way transmitted into the Middle Ages and, eventually, into the present day.

Answer 3

According to The Online Etymological Dictionary, "chromatic" means colorful (as expected) and was introduced into English between 1830 and 1880 to mean "notes adding color" as accidentals. They also say it's not clear why the Greeks used "chromatic" for one of their tetrachords.

"Diatonic" seems to be used in Western Music theory from about 1690 meaning "pertaining to the diatonic scale." The word "diatonic" comes from Greek roots meaning "stretch" and "across" (which doesn't help much.)

Answer 4

This isn't a music theory question, and there is no answer.

Why is a dog called "dog" in English, but "inu" in Japanese, etc. etc?

How do you describe the difference between crimson and vermillion without circular references to red?

Color are described as "warm" and "cold" even though color does not have temperature. People do that, because you can't describe color objectively other than a wavelength frequency. Even names like "green", "red", etc. are subjective. Where does green start and end on the spectrum?

Pitch is describe with various terms like "high" and "low", even though pitch doesn't have elevation. Objectively, pitch, like color, can only be described as a wavelength frequency. Music theory terms like "diatonic" and "chromatic" are fairly objective (although there is an argument about what diatonic means) but they refer to a system of pitches.

Why was the sense of sight, color, invoked to describe the concept of non-diatonic with the label "chromatic?"

Why is the sense of taste, spiciness, often invoked to describe the concept of dissonance?

These ideas are just metaphors. There is no logical reason to choose one particular metaphor over another or to explain the origin of the terminology. The terms could have just as well been "native", "foreign", and "exotic" instead of "diatonic", "chromatic", and "accidental", and the labels would work just fine even though pitches don't have Nationalities. Selecting a metaphor is arbitrary.

You also won't be able to pinpoint and origin for the terminology. Language emerges collectively out of a culture. The best you will be able to find for origin is earliest known (usually printed) usage. You might also find treatises, manifestos, etc. for the origin of terms. Examples from visual art like "Futurism" or "Dada" come to mind. But you still face the conundrum of such terms being in use before the publication.

There is no logical and historical answer.

That isn't satisfying.

If you want something that might satisfy the "why" of the linking, you might consider that the senses of sight and sound both deal with wavelength frequencies unlike taste, smell, and touch. Of course that isn't a historic understanding, but it does explain in part why the senses of sight and sound might be metaphorically linked.