Blog Essay

Etymology of Indo-European Colors

Benji Asperheim and ChatGPT Tue Oct 21st, 2025

How Indo-European color words evolved: blue via Arabic and Frankish, orange via the fruit, yellow/green's ghel- blur, red's reudh- vs. kras-, and black/white from bhel-.

Color words in Indo-European aren’t just labels—they’re fossils of how people carved up light, warmth, and matter. Track them back to Proto-Indo-European (PIE) and you don’t get a single “color system,” you get a cluster of shine/burn roots that different daughters froze at different points on a brightness—warmth continuum. That’s why yellow and green blur around *ghel- (gleam/gold/leaf), why black and white both fall out of *bhel- (burn/shine), and why red splits between *reudh- (blood) and Slavic kras- (beauty → red).

The modern stories fit neatly into that map: blue in French comes from Frankish blao while Spanish azul rides in via Arabic al-lazaward (Lapis lazuli); orange becomes a color only after the fruit arrives; yellow splinters early across branches; red is ancient and culturally loaded; and black/white paradoxically share a “fire” ancestor. The result isn’t chaos—it’s a readable pattern of semantic drift plus contact and trade.

💙 ‘Blue’ in Indo-European Languages

The Latin color words for blue were caeruleus (sky-blue) and lividus (grayish-blue). Those continued in some Romance descendants (Italian celeste, French céruléen, etc.), but not as the ordinary everyday word for “blue.”

Old French line (bleu): The Frankish blao → Old French bleu replaced Latin caeruleus in the north, probably due to Frankish (Germanic) influence. → Modern French bleu, English blue, Dutch blauw all come from that same Germanic blao root.
Spanish line (azul): The Visigoths brought Germanic influence too, but the everyday Spanish term azul doesn’t come from that. It’s from Arabic الزورد (al-lazaward) → Persian lajvard → meaning “lapis lazuli,” the blue stone. From that, medieval Spanish azur / azul arose, paralleling French azur (“sky blue”).
- Arabic al-lazaward → Old Spanish azur → azul
- Same origin as English azure and French azur

So:

French “bleu” ← Germanic (blao)
Spanish “azul” ← Arabic (al-lazaward)
Latin “caeruleus” is the older classical color term that mostly fell out of common use in both cases.

👉 azul is a loanword from Arabic, while bleu is a Frankish/Germanic loan — both replaced the older Latin term in their respective languages.

🧡 ‘Orange’ in Indo-European Languages

“Orange” is a borrowed concept and color term that entered Europe relatively late.

Sanskrit nāraṅga → Persian nārang → Arabic nāranj → Old Italian arancia → Old French orenge/orange → English orange, Spanish naranja.

Before oranges (the fruit 🍊) arrived in medieval Europe via Arab trade, the color wasn’t even conceptually distinct in most languages. People described orange things as “red”:

Old English geoluread (“yellow-red”) for orange shades.
In Old Norse, rauðr (“red”) covered reddish-orange tones.
Slavic and Germanic languages followed similar patterns.

After the fruit became common, its name became the color name — just like “salmon” or “cherry” in English.

So, the color term orange emerged only after the fruit spread through the Mediterranean via Arabic and Persian trade routes, roughly between the 10th and 13th centuries.

💛 ‘Yellow’ and 💚 ‘Green’ in Indo-European Languages

Why does “yellow” look so different across various Indo-European languages?

Unlike very stable color words such as black, white, or red, the word for yellow diverged early across Indo-European branches because it was semantically unstable — it overlapped with “bright,” “pale,” and “golden.”

That’s why Romance, Germanic, and Slavic languages all use different reflexes for this concept.

Language	Word	Origin
German	gelb	Proto-Germanic gelwaz “yellow, golden,” from PIE ǵʰelh₃- “to shine, gleam”
English	yellow	Same root: gelwaz → OE geolu
Dutch	geel	Same as above
Latin → Romance	galbinus (“pale green/yellowish”) → giallo (It.), jaune (Fr.), amarillo (Sp.)
Greek	xanthos (“golden, blond”)	From PIE ǵʰséndʰos (related root meaning “bright”)
Slavic	želtŭ (Rus. žëltый)	Also from PIE ǵʰelh₃- “to shine,” same family as Germanic
Sanskrit	hari-, pīta-	Various roots for “yellow, tawny,” also “bright” or “golden”

Germanic and Slavic “yellow” words are true cognates, both tracing to the PIE root ǵʰelh₃- (“to shine, gleam, greenish-yellow”).
Romance words mostly don’t descend from that root — Latin lost it and innovated new terms (galbinus, flavus, luteus, etc.), later replaced in vernaculars by derivatives like jaune, giallo, amarillo.

Etymology of German gelb

Proto-Indo-European: ǵʰelh₃- = “to shine; yellowish-green; gold-colored.”
Proto-Germanic: gelwaz = “yellow.”
Old High German: gelb or gelwe.
Modern German: gelb.

So gelb is actually a very ancient Indo-European inheritance, not a later innovation. It’s the same root that produced gold (gulþą in Proto-Germanic — same PIE ǵʰelh₃-).

That’s why gold and yellow are etymologically linked in many languages.

You can still see the pattern:

gelb ↔ gold ↔ “gleam / glow” → PIE ǵʰelh₃-

That also explains why gelb feels “different” from jaune or giallo — it’s a Germanic survival of the “shine/gleam” root, while Latin/Romance replaced theirs with new adjectives for “pale” or “golden.”

Why are Romance Words for ‘Yellow’ so Different?

Latin had flavus (yellow, blond), luteus (yellowish), and galbinus (greenish-yellow). But in Vulgar Latin, regional preferences diverged:

In the West, galbinus → Old French jaune.
In Italy, galbinus → giallo.
In Iberia, amarus (“bitter”) → amarillo (from amarellus, diminutive of amarus, maybe via “pale, sickly” → “yellowish”).

Conceptual Blur Between Yellow and Green

Human perception naturally links green, yellow, and brightness because they all occur on the “luminous” end of the color spectrum — bright sunlight, gold, fresh grass, ripening leaves. Many languages (even outside Indo-European) originally used a single term for this whole zone before differentiating it.

Examples:

In Old English, geolu-grēne = yellow-green.
In Japanese, aoi originally meant “blue/green” before midori specialized for “green.”
In Old Irish, glas could mean green, blue, or gray.
In Old Russian, зеленъ (green) and желтъ (yellow) both derive from ghel-.

This is a universal perceptual drift: languages sharpen boundaries only when needed — e.g., for dyes, trade, or art.

Color terms tend to be conceptually fluid until a society stabilizes on consistent pigment categories. “Yellow” was especially fuzzy — overlapping with:

blond (hair)
golden (metallic hue)
pale or light (light skin, old paper)
greenish (young leaves)

The Proto-Indo-European root ǵʰelh₃- (sometimes written ghel- or gʰel-) meant something like → “to shine,” “to gleam,” “to be bright green/yellow.”

From that single root, you get descendants that diverged in meaning toward green, yellow, gold, and even light — depending on what aspect the language emphasized.

Concept	Derived Words	Languages
Yellow	gelb, geel, yellow, żółty	German, Dutch, English, Polish, etc.
Green	green, grün, gjelbër (Alb.)	Germanic, Albanian
Gold	gold, guld, oro (via analogy)	Germanic
Bright / Light	hell (Ger.), halo, gleam, glow	Germanic, Greek, English
Shine / Glow	glänzen, glitter, glisten	Germanic

So the same Proto-Indo-European ghel- root gave rise to gelb (yellow), green, and hell (bright). They’re cognates, though they split semantically early. That’s why “yellow” words vary so much even among languages that otherwise share conservative roots for other basic colors.

The Latin “galbinus” Connection

Latin galbinus = “greenish-yellow,” from galbus “pale green/yellowish.”
Etymologically, galbus < PIE ghel- as well.
So galbinus sits right in that fuzzy middle zone — where yellow and green blend. → Think of chartreuse or young leaves: neither fully yellow nor green.

Romance languages later split that semantic space:

verde (from Latin viridis) → “green”
flavus/luteus or galbinus descendants → “yellow”

But Albanian preserved the old overlap, using gjelbër and jeshile (from the same root area) to cover greenish tones — both ultimately traceable to that Indo-European ghel- root too.

It reflects an older stage of PIE color categorization where “green,” “yellow,” and “bright” weren’t sharply distinguished. So Albanian didn’t “mix them up”—rather it’s more conservative.

German hell and its Relatives

German hell (bright, light) is from the same PIE root ghel- “to shine.”

The German word ‘hell’ is directly related to gelb, gold, glänzen, glühen, glanz, glitter, glow, etc. hell and gelb are cognate siblings from the same ancestral root, which originally covered brightness, yellow-green hue, and shining surfaces (like gold, light, or fresh vegetation).

So German gelb does not come from Latin galbus—they’re cognates or independent descendants of the same PIE root:

PIE	Proto-Germanic	Old High German / Modern	Latin	Meaning
ǵʰel- / ghel- “shine, yellow-green”	gelwaz	gelb	galbus → galbinus	shining, yellowish, greenish

Both developed separately from the common ancestral ghel- root, which originally meant “to shine, gleam” — often with a yellow-green-gold nuance (as in sunlight, leaves, or gold). So yes, the gelb—galbus—galbinus cluster is exactly where that blur between yellow and green sits.

Below is a unified, detailed comparative chart that merges the “golden-green” ghel-family, and the other “shine” roots (bhereg-, leuk-, bhel-, yer-, etc.), including German hell and Albanian shkëlqim.

🌞 The Indo-European “Shine” Family: Comparative Map

Semantic Zone	Proto-Indo-European Root	Core Meaning / Imagery	Notable Reflexes (Examples)	Descendant Languages	Notes
Golden / Greenish Shine	*ǵʰel-, ghel-, gʰl-*	to shine, gleam, glow yellow-green; bright like gold, fresh leaves, sunlight	Ger. gelb (yellow), glänzen (shine), glühen (glow), Glanz (brightness), hell (light, bright); Eng. yellow, gold, glow, gleam, glitter; Lat. galbus, galbinus (greenish-yellow); Gk. χλωρός (chloros, green, pale); Alb. shkëlqej, shkëlqim (shine, brilliance); Sla. želtъ (yellow)	Germanic, Italic, Hellenic, Albanian, Slavic	This is the “warm” light root — spanning yellow, gold, and green. Source of gold and yellow; metaphorically linked to vitality and vegetation. Albanian shkëlqim and Slavic želtъ are distant cognates.
White / Clear Brightness	bhereg-	to shine, be white, clear, pure light; brightness itself	Eng. bright; Ger. berht, beraht, names like Albert (“noble-bright”), Bertha; ON. bjartr (bright, clear)	Germanic	This is “white brilliance,” like sunlight or polished metal. Distinct from ghel- (warm/yellow); bhereg- is cool, clear, dazzling light.
Daylight / Illumination	leuk-	light, brightness, illumination	Lat. lux, lumen, lucid, illuminate; Gk. λευκός (leukos, white); Eng. light (via Proto-Germanic leuhtą); Sla. světъ (“light,” from the same semantic field)	Italic, Hellenic, Germanic	The “light itself” root — associated with visibility and daylight, not color. Gave most Romance “light” terms and lucid, illuminate, translucent.
Flashing / Fiery / Burning Light	bhel-, bhelH-*	to flash, burn, shine brightly; flare up	Eng. flame, blaze, bleach, blush, bloom, flash; Lat. fulgere (to shine), flamma (flame), fulmen (lightning); Skt. bhā- (shine); Rus. белый (belyj, “white”)	Widespread (Germanic, Italic, Indo-Iranian, Slavic)	The “flame” root — denotes light-emitting combustion. Often shifts to “white” or “pale” (Slavic belyj). Source of many “burning / bright” metaphors.
Fiery / Vivid / Ardent Brightness	yer-, jar-*	vivid, vigorous, bright, fiery	Rus. яркий (bright), ярость (fury), Ярило (solar deity, “Radiant One”)	Slavic	Denotes energetic radiance, not mere light — vivid intensity, passion, strength. Color metaphor expanded to describe temperament.
Red / Glowing / Beautiful Brightness	kras-, ker-*	beautiful, shining, red, ornate	Rus. красный (red), красивый (beautiful); OCS krasъ (beauty)	Slavic	Replaced rъdъ (from reudh-) as the color term “red” due to association between beauty and rosy coloration.
General Light / Fire / Shine	bher-	to shine, burn, brownish light	Eng. burn, brown; Gk. pharos (beacon)	Germanic, Greek	Transitional “warm” root between brightness and heat; tied to smoldering glow.

🟡 Highlights and Connections

German “hell” and “gelb” → Both from ghel-, “shine, yellow-green.” Hell (“light, bright”) is the semantic “luminous” offshoot; gelb (“yellow”) is the chromatic one. Cognates: glow, gleam, glitter, gold, glänzen, glühen.
Albanian “shkëlqim / shkëlqej” → Also from ghel-, “to shine.” Through Proto-Albanian skel- → modern shkël-. Cognate to gelb, glow, glänzen, etc.

Semantic Continuum Across PIE:

[Fire / Flash (*bhel-*)]
       ↓
[White / Clear (*bhereg-*, *leuk-*)]
       ↓
[Yellow / Green (*ghel-*)]
       ↓
[Red / Beautiful (*kras-*, *reudh-*)]
       ↓
[Fiery / Vivid (*yer-*)]

→ Indo-Europeans conceived light and color along a brightness + warmth spectrum, not as discrete hues. Each branch fossilized a different point of that continuum into vocabulary.

Cultural & Symbolic Layers:
- ghel- = gold, sunlight, vegetation → prosperity, vitality
- bhereg- = clarity, nobility → “bright fame” (Albert, Bertha)
- leuk- = enlightenment, knowledge (lucid, illuminate)
- bhel- = fire, transformation (flame, blaze)
- yer- = vigor, intensity (яркий, ярость)
- kras- = beauty and life (красный, красивый)

🧩🌼⭐️ Green/Yellow/Bright/Shiny Summary

Root	Meaning Range	Representative Modern Words	Core Image
ghel-	gleam, yellow-green brightness	gelb, hell, glow, glänzen, shkëlqim, chloros, galbinus	sunlight, gold, leaves
bhereg-	white-clear brightness	bright, bjartr, Albert, Bertha	shining metal, clean light
leuk-	light, illumination	lux, lumen, lucid, leukos, light	daylight, enlightenment
bhel-	flash, burn	flame, blaze, bleach, fulgere	fire, lightning
yer-	vivid, fiery	яркий, ярость, Jarilo	intense radiance, passion
kras-	shining beauty / redness	красный, красивый	beauty, youth, rosy hue
reudh-	blood-red	red, rojo, ruber, rudhira, erythros	blood, life force

❤️ ‘Red’ in Indo-European Languages

Red is an important one, because it is among the most stable and culturally charged color words in Indo-European. It’s ancient, but its story branches sharply: the red of blood vs. red as beautiful / shining.

Let’s dig into the three main PIE roots that fed the various “red” words across Indo-European:

🩸 1. PIE h₁reudh- / reudh-* → “red (blood-colored)”

This is the *canonical PIE color root for “red.”, and it’s the one that gave most Indo-European languages their core “red” term.

Basic meaning: “red, ruddy, blood-colored.” Semantic field: blood, rust, skin tone, metal (copper, bronze).

Branch	Reflex	Modern forms / Notes
Germanic	rauthaz	Eng. red, Ger. rot, Du. rood, Icel. rauðr
Latin / Italic	ruber, russus, rufus	It. rosso, Sp. rojo, Fr. rouge
Celtic	ruadh	Ir. rua, Sc. Gael. ruadh
Baltic	raud-as, raud-onas	Lith. raudonas, Latv. sārts (slightly shifted)
Slavic	rъdъ → rьdъ, ruda	OCS rъdъ, but main color term replaced (see below)
Tocharian	rotse, ratsi	Same root
Sanskrit	rudhira, rudra, rohitá-	red, blood-colored, name of the storm god Rudra
Avestan	raodha-	red, ruddy

So Spanish rojo, French rouge, and English red are all direct descendants of this PIE reudh- root, each through a different daughter branch.

🌹 2. Slavic exception: красный (krasnyj)

Here’s the twist: Russian “красный” originally didn’t mean “red” at all. It meant “beautiful.”

Proto-Slavic	krasъ	”beautiful, splendid, ornate”
PIE source	ḱer- / kers- / kras-?	“shine, glow, be beautiful”

The old Slavic word for “red” was ръдъ / rъdъ (from reudh-), but over time it fell out of use as красный took over the color meaning.

This shift happened because “beautiful” and “red (rosy, lovely)” were culturally linked — especially in reference to healthy skin, youth, and ornamentation.

That’s why in Slavic:

красивая (krasivaya) = “beautiful”
красный (krasnyj) = “red”
красота (krasota) = “beauty”
Красная площадь (Krasnaya ploshchad’) = literally “Beautiful Square,” not “Red Square” originally

So in Russian, red = “the beautiful color.” The original rъdъ root survives fossilized in words like руда (“ore,” i.e., reddish rock).

Albanian took a different route:

Albanian kuq (adj.), e kuqe (fem.) = red
Derived from PIE **kʷeik- / kʷouk- / kouk- meaning “bright, flaming, reddish,” possibly echoic (onomatopoetic) of “burning, glowing.”

Compare:

Language	Form	Meaning
Alb.	kuq	red
Latin	coccinus (from Gk. kokkos, berry)	scarlet
Greek	kokkinos, kokkos	red, scarlet (from “berry”)
Proto-Slavic	kъkъ (rare, onomatopoetic “burn”)	possibly connected

Some etymologists think kuq could be borrowed early from a pre-Latin or Illyrian substrate, or that it continues an archaic PIE kouk- “fiery red.”

It’s not from reudh- directly, but fits the same color zone (flame, blood).

So Albanian kuq = same semantic region as reudh-, but a separate lineage.

🔥 4. A few other PIE “reddish” roots worth noting

Root	Meaning	Examples
bher- “brownish-red, bright”	Eng. burn, brown
rudh- / reudh- “blood-red”	red, rojo, ruber
ker- / kras- “shine, beauty”	красный, красота
kok- / cocc- “berry-red”	Gk. kokkinos, Lat. coccinus, Alb. kuq (possibly)

🩸 TL;DR

The core Indo-European “red” root is reudh- (“blood-colored, ruddy”). → red, rot, rojo, rouge, ruber, rudhira, erythros, ruadh, raudonas.
Slavic languages replaced it with a native root meaning “beautiful” → “red.” красный = “beautiful color.”
Albanian kuq may be from an older or parallel PIE *kouk- / kʷeik- root meaning “burning, glowing red,” possibly shared with Greek kokkinos.
So across Indo-European, “red” sits at the intersection of blood, fire, and beauty — the most symbolically loaded color in every branch.

Language	Word	Root	Original sense
English	red	PIE reudh-	blood-colored
German	rot	reudh-	same
Spanish	rojo	reudh- → Lat. russus	same
Latin	ruber / russus / rufus	reudh-	red, reddish-brown
Russian	красный	kras- “beautiful”	beautiful → red
Albanian	kuq	possibly kouk- “glowing red”	fiery, red
Sanskrit	rudhira, rohitá	reudh-	red, blood
Greek	erythros	reudh-	red
Irish	ruadh	reudh-	red, ruddy
Lithuanian	raudonas	reudh-	red

🖤 ‘Black’ and 🤍 ‘White’ in Indo-European Languages

We’ve now come full circle through the Indo-European color spectrum, and landed on one of the most paradoxical but revealing pairs: white and black, both of which ultimately go back to the same PIE root for “shine, burn, blaze.”

Let’s close the loop properly and tie this into the earlier “light—color continuum” map.

1. PIE Root *bhel- (1) — “to shine, flash, burn”

This single root gives rise to both ends of the visual spectrum — black and white — depending on whether the semantic focus was on:

🔥 the act of burning / fire → darkened, charred, black
✨ the brightness / gleam of flame → shining, white

That split is the key to understanding why “black” and “blank” are, etymologically, siblings.

🔥 DARK BRANCH — “burned, sooty, black”

Language / Word	Meaning	Derivation Path
OE blæc → Eng. black	dark, soot-colored	PIE bhel- → PGmc blakaz “burned, scorched” → OE blæc
OHG blah	black	same root
ON blakkr	dark, blackish	same
Dut. blaken	to burn, scorch	same
Eng. bleak	originally “pale, shining” → later “cold, dreary”	parallel semantic drift; same root

So “black” literally means “burned thing” — something that once shone but is now charred. It’s the shadow of brightness encoded in the same root.

✨ LIGHT BRANCH — “bright, shining, white”

Language / Word	Meaning	Derivation Path
OF blanc → Eng. blank	white, shining	PIE bhel- → PGmc blangkaz “shining, bright” → OF blanc
Ger. blank	shiny, polished	same
Sp. blanco	white	from Frankish blank
Alb. bardhë	white	separate branch of bhel- with metathesis (bherdʰ-)
Slav. bělъ → Rus. белый (belyj)	white	PIE bhel- → PS bělъ “white, shining”

These are the same family as black, but through the “shining white” sub-branch. Notice how both belyj and blanco preserve the bl- consonant cluster from PIE bhel-.

So PIE bhel- created a semantic gradient:

bhel- → blaze → burn → blackened bhel- → shine → gleam → white

2. PIE Root **bheig- / bhleg- — “burn, flash, gleam”

Closely related (and sometimes merged with bhel-), this root gives:

Lat. flagrare “to blaze” → conflagration
Grk. phlegein “to burn, scorch” (as you quoted)
Eng. black again, through the “burned” sense

So you can imagine two intertwined roots: bhel- (shine) and bhleg- (burn), feeding both brightness and darkness.

3. PIE Roots for “White / Bright” (Distinct but Overlapping)

Besides bhel-, a few others specialize in paleness or purity:

PIE root	Core meaning	Descendants
leuk-	light, brightness	lux, lucid, leukos, light
bher-t- / bher-g-*	bright, clear	bright, Bertha
arg-	shining white, silver	argentum, Argos, arjuna (Skt.)
cand-	to glow, be white	candid, incandescent
weis-	bright, shining, white	white, wheat (“the white grain”)

These roots often overlapped; “white” and “bright” were conceptually one category — visible, shining, pure.

4. PIE Roots for “Dark / Black”

PIE root	Core meaning	Descendants
swér-t- / sword-*	dark, black	OE sweart (swarthy), Ger. schwarz
mel- / smel-	dark, sooty	mélas (Gk. “black”), melancholy (“black bile”)
bhleg- / bhel-*	burned, charred	black, blakkr
nebh-	cloud, mist	nebulous, nimbus

So Germanic had two “black” words:

sweart (the older native term, cf. swarthy)
blæc / black (the “burned-dark” innovation from bhel-).

5. Russian “чёрный” (čërnyj)

From Proto-Slavic čĭrnŭ ← PIE *ker- / sker- “dirty, darkened, sooty.” Same family as charcoal, scorch, skorched (possibly through a similar s-extension).
So, no relation to cherry 🍒 — pure coincidence in sound. Cherry is from Latin cerasum (fruit from Cerasus in Pontus, Anatolia). → черный and cherry only look alike by chance.

6. Wrapping It Back Into the “Shine Spectrum”

Color / Light Zone	PIE Root(s)	Conceptual Focus	Modern Reflexes
Bright White / Luminous	leuk-, bhereg-, cand-, arg-, bhel- (light sense)	shining, pure, visible	light, lucid, bright, blanc, belyj, bardhë
Golden / Yellow-Green	ghel-	glowing, sunlit, vital	gelb, yellow, chloros, shkëlqim
Fiery / Red / Beautiful	reudh-, kras-, yer-	blood, beauty, flame	red, rojo, krasnyj, яркий
Dark / Burned / Black	bhel- (burned), swert-, mel-	soot, shadow, absence of light	black, schwarz, čërnyj, melas

→ bhel- is the bridge between white and black, generating both extremes by focusing on the fire that either burns brightly or chars to darkness.

🔦 TL;DR Summary of PIE Black & White

“Black” and “blank / blanco / bardhë / belyj” are etymological opposites born from the same PIE root *bhel- “to shine, burn.”

bhel- (shine) → blank, blanco, belyj, bardhë = “white, bright.”
bhel- (burn) → black, blakkr = “burned, charred, dark.”
Other “white” roots (leuk-, arg-, cand-) specialized for clarity or metallic brightness.
Other “black” roots (swert-, mel-, ker-) specialized for darkness, soot, or filth.
Russian чёрный has nothing to do with “cherry”; it’s from ker- / sker- “dirty, dark.”

So, Indo-Europeans conceptually framed black and white not as opposites but as two outcomes of the same phenomenon — fire and light:

🔥 bhel- → the blaze that either dazzles white or leaves ash black.

Conclusion

Indo-European color words aren’t a tidy palette—they’re a set of overlapping shine/burn lineages that languages specialized differently:

Blue split paths: a Germanic “bleu/blue” corridor from Frankish blao, and Spanish azul via Arabic al-lazaward (lapis).
Orange only becomes a color term after the fruit spreads through Persian/Arabic trade; before that, languages stretched red/yellow.
Yellow/Green live in the same PIE neighborhood: *ghel- “gleam, gold, leaf”—the source of German gelb, Greek chloros, Albanian shkëlqim (shine), and cognate to German hell (bright).
Red mostly reflects *reudh- (blood) across branches (red/rot/rojo/rouge), while Slavic famously repurposes kras- (“beautiful”) to mean red.
Black/White both ride out of *bhel- (“burn/shine”): burned → black, gleaming → blank/blanco/belyj/bardhë—the same fire seen from opposite ends.

Zooming out, the system is coherent: PIE organized color around light behavior (shining, burning, gleaming) and salient materials (blood, gold, flame, stone). Later contact (Frankish, Arabic, Persian) and technological change (dyes, trade goods) nudged boundaries and swapped everyday terms. If you picture a spectrum cool-white → yellow-green → fiery-red with “burn” straddling both shine and soot, today’s words stop looking arbitrary—they’re just fossilized checkpoints along that old continuum.

Sources

General Color Terms

Berlin & Kay, Basic Color Terms (Wikipedia overview) — https://en.wikipedia.org/wiki/Basic_Color_Terms
Color term (linguistics) — https://en.wikipedia.org/wiki/Color_term