is the color
evoked by light that stimulates both the L
(long and medium wavelength) cone cells
of the retina
about equally, but does not significantly stimulate the S
(short-wavelength) cone cells; that is, light with much red
but not very much blue
. Light with a wavelength of 570–580 nm
is yellow, as is light with a suitable mixture of somewhat longer and shorter wavelengths. Yellow's traditional RYB complementary color
. Yellow's colorimetrically defined complementary color in both RGB
color spaces is blue
Electric yellow vs. process yellow
The color box at right shows the most intense yellow representable in in 8-bit RGB color model; yellow is a secondary color in an additive RGB space.
The measured light spectrum from yellow pixels on a typical computer display is complex, and very unlike the reflectance spectrum of a yellow object such as a banana.
Process yellow (also known as pigment yellow, printer's yellow or canary yellow) is one of the three colors typically used as subtractive primary colors, along with magenta and cyan. The CMYK system for color printing is based on using four inks, one of which is a yellow color. This is in itself a standard color, and a fairly narrow range of yellow inks or pigments are used. Process yellow is based on a colorant that reflects the preponderance of red and green light, and absorbs most blue light, as in the reflectance spectra shown in the figure on the lower right.
Because of the characteristics of paint pigments and use of different color wheels, painters traditionally regard the complement of yellow as the color indigo or blue-violet.
Process yellow is not an RGB color, and there is no fixed conversion from CMYK primaries to RGB. Different formulations are used for printer's ink, so there can be variations in the printed color that is pure yellow ink.
Etymology and definitions
The word yellow
comes from the Old English geolu
, or geolwe
which derived from the Proto-Germanic
. The oldest known usage of this word in English is in the Old English poem Beowulf
, in a description of a shield made of wood from a yew tree
. In the English language, yellow is used to describe objects having the color between green and orange in the visible light spectrum (gold
, egg yolks, sunflowers, etc.). The color is associated with age and aging, both with people and objects (e.g. yellowed-paper). Ethnographically, the term yellow has also been used as a slang term for both oriental persons and light-skinned African-Americans. The term is associated at times with jealousy, as well as cowardliness. Lastly, it is associated with sensational journalistic practices, or yellow journalism
, and resistance to militant trade unions.
Complements of yellow
Hunt defines that "two colors are complementary when it is possible to reproduce the tristimulus values of a specified achromatic stimulus by an additive mixture of these two stimuli." That is, when two colored lights can be mixed to match a specified white (achromatic, non-colored) light, the colors of those two lights are complementary. This definition, however, does not constrain what version of white will be specified. In the nineteenth century, the scientists Grassmann and Helmholtz did experiments in which they concluded that finding a good complement for spectral yellow was difficult, but that the result was indigo, that is, a wavelength that today's color scientists would call violet. Helmholtz says "Yellow and indigo blue" are complements. Grassman reconstructs Newton's category boundaries in terms of wavelengths and says "This indigo therefore falls within the limits of color between which, according to Helmholtz, the complementary colors of yellow lie. Newton's own color circle has yellow directly opposite the boundary between indigo and violet. These results, that the complement of yellow is a wavelength shorter than 450 nm, are derivable from the modern CIE 1931 system of colorimetry if it is assumed that the yellow is about 580 nm or shorter wavelength, and the specified white is the color of a blackbody radiator of temperature 2800 K or lower (that is, the white of an ordinary incandescent light bulb). More typically, with a daylight-colored or around 5000 to 6000 K white, the complement of yellow will be in the blue wavelength range, which is the standard modern answer for the complement of yellow.
Plants and animals
- The yellow birch (Betula alleghaniensis) is a birch species native to eastern North America, from Nova Scotia, New Brunswick, and southern Quebec west to Minnesota, and south in the Appalachian Mountains to northern Georgia. They are medium-sized deciduous trees and can reaching about 20 m tall, trunks up to 80 cm in diameter. The bark is smooth and yellow-bronze and the wood is extensively used for flooring, cabinetry, and toothpicks.
- Yellow-breasted Chats (Icteria virens) are large foraging songbird found in southern parts of Canada, the United States, Mexico, and Central America. They are olive with a white bellies and a yellow throat and breast, with a long tail, a thick heavy bill, a large white eye ring, and dark legs.
- A yellow-fever mosquito is a mosquito in the Aedes genus, so named because they transmit dengue fever and yellow fever, the mosquito-born viruses.
- Yellow-green alga, also called xanthophytes, are a class of algae in the Heterokontophyta division. Most live in freshwater, but some are found in marine and soil habitats. They vary from single-celled flagellates to simple colonial and filamentous forms. Unlike other heterokonts, yellow-green algae's chloroplasts do not contain fucoxanthin, which is why they have a lighter color.
- The Yellowhammer (Emberiza citrinella) is a passerine in the bunting family Emberizidae. It breeds across Europe and much of Asia. Most yellowhammers are resident, but some far northern birds migrate south in winter. It is common in all sorts of open areas with some scrub or trees. They are large with a thick seed-eater's bill. The males have a bright yellow head, yellow underparts, and a heavily streaked brown back. Females are much duller and more streaked below.
- Yellowjackets are black-and-yellow wasps of the genus Vespula or Dolichovespula (though some can be black-and-white, the most notable of these being the bald-faced hornet, Dolichovespula maculata). They can be identified by their distinctive black-and-yellow color, small size (slightly larger than a bee), and entirely black antennae.
- Yellow poplar is a common name for Liriodendron, the tuliptree. The name is inaccurate as this genus is not related to poplars.
- The Yellow-shafted Flicker (Colaptes auratus) is a large woodpecker species of eastern North America. They have yellow shafts on their wing and tail feathers.
- Yellowtail is the common name for dozens of different fish species that have yellow tails or a yellow body.
- Goldenrod is a yellow flowering plant in the Family Asteraceae
- A Yellow Labrador Retriever refers to the lightest color that occurs in the breed, lighter than chocolate and back Labrador retrievers.
Yellow in human culture
- Yellow is associated with Monday on the Thai solar calendar. Anyone may wear yellow on Mondays, and anyone born on a Monday may adopt yellow as their color.
- In the English language, yellow has traditionally been associated with jaundice and cowardice. In American slang, a coward is said to be "yellowbellied" or "yellow".
- "Yellow" ("giallo"), in Italy, refers to crime stories, both fictional and real. This association began about in 1930 because the first series of crime novels published in Italy had a yellow cover.
- Pencils are often painted yellow, originally because of the association of this color with the Orient, where the best graphite was found.
- The phrase "Yellow Yellow, dirty fellow" is used by children to mock someone wearing yellow.
- Yellow movies = blue movies in Chinese (黃色電影) reference:
- Asian people are sometimes referred to as the yellow race. The use of "yellow" to refer to people of East Asian descent is usually regarded as offensive today in most contexts. In early 20th-century North America, immigrants from China and other East Asian nations were derogatorily referred to as a "yellow peril."
- A High yellow is African-American slang for someone who is a very light-skinned African-American. This term was widely used in the early 20th century but it is seldom heard nowadays.
- Yellow is the color of the snooker ball that has a 2-point value.
- A semi-popular game in the UK is "Yellow Car", which involves yelling "Yellow Car" and striking someone close to you on spotting a yellow car. There are multiple variations of this game depending on area or group played with, but the above is the common rule between them.
- Yellow is associated with jaundice, since someone who has that disease may turn yellow.