The Official Register of Color Names files every color under one of thirteen Color Families. Those thirteen names are precise, and two of them — Chartreuse and Azure — are words most people never use. This article is about the other names: the ones people actually type into a search box, and how they relate to the ones the Register uses.
Why a Category Needs More Than One Name
The twelve hue families are the twelve equal sectors of the color wheel, and their names come from the wheel itself: Red, Orange, Yellow, Chartreuse, Green, Spring Green, Cyan, Azure, Blue, Violet, Magenta, Rose. That is the vocabulary of color theory, and it is the right vocabulary for a classification, because each name marks an exact 30° position.
It is not, however, the vocabulary of everyday speech. Nobody describes a shirt as azure. They say ocean blue, or sky blue, or cobalt — three different words for one 30° sector.
So the Register keeps two things apart. The family name is canonical: one color, one family, no ambiguity. Alternative names sit above it — several per family, none of them official, all of them useful for finding your way around.
The Thirteen Families and Their Alternative Names
| Color Family | Center | Also known as |
|---|---|---|
| Red | #FF0000 | Pink · Crimson · Scarlet · Coral · Ruby |
| Orange | #FF8000 | Brown · Gold · Beige · Peach · Tan · Amber |
| Yellow | #FFFF00 | Gold · Olive · Lemon · Lime · Cream |
| Chartreuse | #80FF00 | Lime · Pistachio · Harlequin |
| Green | #00FF00 | Emerald · Malachite · Fern |
| Spring Green | #00FF80 | Mint · Aquamarine · Seafoam · Sea |
| Cyan | #00FFFF | Turquoise · Teal · Aqua · Opal · Cerulean |
| Azure | #0080FF | Ocean · Cobalt · Cornflower · Sky · Sapphire |
| Blue | #0000FF | Navy · Indigo · Sapphire |
| Violet | #8000FF | Purple · Indigo · Lavender · Lilac |
| Magenta | #FF00FF | Purple · Orchid · Fuchsia · Mulberry |
| Rose | #FF0080 | Pink · Raspberry · Cerise · Plum |
| Greyscale | #808080 | Black · White · Grey · Gray · Silver · Charcoal · Ash · Slate |
Bold entries are the ones worth knowing about, because they are more common in ordinary use than the canonical name itself. More people search for turquoise than for cyan, and for purple than for violet.
An Alias Is Not a Synonym
An alternative name points at a family; it does not replace it, and it is rarely a perfect fit. Three cases are worth separating.
Names that sit inside a family
Turquoise #40E0D0 has a hue of about 174°. That is inside the Cyan sector (165–195°), but nowhere near its center. Turquoise is a region of Cyan, not another word for it — and the same is true of Teal, Aqua and Cerulean, which all crowd into the same part of the same sector.
Names that straddle two families
Purple is the clearest case. In the Register, colors named “Purple” land in Violet more often than in Magenta, but plenty land in each. There is no hue angle at which purple begins and ends; the word simply covers the seam between two families.
Names that are not hue names at all
Brown is not a position on the wheel. It is what a dark, muted orange looks like — and sometimes a dark red or a dark yellow. Take Sandy Brown #F4A460, which is 67% light: brown by name, but far too bright to sit where a dark-orange rule would put it. Any attempt to define brown as a range of hue and lightness gets roughly half the cases wrong, which is why the Register does not try.
How This Shows Up on the Site
The distinction produces two kinds of list, and they answer two different questions.
Family lists are built from the classification. Shades of Cyan holds every color in the 165–195° sector, whatever it happens to be called. It answers: which colors are Cyan?
Name lists are built from the names. A list of turquoise color names holds every registered color with “Turquoise” in its name, wherever it sits on the wheel. It answers: which colors are called turquoise?
The two overlap without being duplicates — one is a region, the other is a word. There are exactly thirteen family lists and there will never be a fourteenth, because there are thirteen families. Name lists are open-ended: any word that enough registered colors share can have one.
Naming Tolerance: The Same Idea, Applied to Names
Alternative names also explain why the Register accepts a name that does not match its family exactly.
Classification is strict, because a color must land in one family and only one. Naming is deliberately generous, because language is. Ocean Blue on an Azure color is accepted, and so is a color word sitting a few degrees outside its range. On a near-grey, a near-black or a near-white, hue words are not checked at all — there is no visible hue to contradict.
The full set of rules — the thirty-five recognised color words, the 8° margin, the achromatic zone, and the lightness rules for black, white and grey — is set out in Understanding Categories of Digital Colors, under Naming Tolerance.
Two layers, deliberately different widths. A strict one for what a color is. A generous one for what it may be called.
ORCN Digital Color Categories, Version 1.1 (ORCN-DCC 1.1)
Alternative names are a navigation layer. They are not part of the classification, and no color is ever filed under one.
