any of various colors resembling the color of blood; the primary color at one extreme end of the visible spectrum, an effect of light with a wavelength between 610 and 780 nanometers.
something red.
Older Slang: Usually Disparaging. Often Red a radical leftist in politics, especially a Communist.
Informal. red light.
Informal. red wine.
a glass of red.
Also called red devil. Also called red bird,. Also called red doll. Slang. a capsule of the drug secobarbital, usually red in color.
He was caught with a half dozen reds in the bottom of his pack of cigarettes.
of the color red; of or like the color of blood.
a red rose.
reddish purple in color.
red wine made from purple grapes.
orange, golden brown, or reddish brown in color.
red hair.
having distinctive areas or markings of red.
a red robin.
red eyes from allergies.
(of the face) flushed or blushing, as from shame.
cheeks red with embarrassment.
of or indicating a state of financial loss or indebtedness.
the red column in the ledger.
Politics. relating to, supporting, or belonging to the Republican Party in the United States; Republican.
This is big news in that it flips a red Senate seat to blue.
Older Slang: Usually Disparaging.
radically left politically.
Often Red communist.
Red China.
Older Use: Disparaging and Offensive. relating to, noting, or characteristic of North American Indian peoples.
see red, to become very angry; become enraged.
Snobs make her see red.
paint the town red. paint.
in the red, operating at a loss or being in debt (opposed to in the black).
The newspaper strike put many businesses in the red.
a male or female given name.
a nickname typically given to someone with red hair.
any of a group of colours, such as that of a ripe tomato or fresh blood, that lie at one end of the visible spectrum, next to orange, and are perceived by the eye when light in the approximate wavelength range 740–620 nanometres falls on the retina. Red is the complementary colour of cyan and forms a set of primary colours with blue and green
a pigment or dye of or producing these colours
red cloth or clothing
dressed in red
a red ball in snooker, billiards, etc
(in roulette and other gambling games) one of two colours on which players may place even bets, the other being black
Also called: inner. archery a red ring on a target, between the blue and the gold, scoring seven points
informal in debit; owing money
informal to become very angry
of the colour red
reddish in colour or having parts or marks that are reddish
red hair
red deer
having the face temporarily suffused with blood, being a sign of anger, shame, etc
(of the complexion) rosy; florid
(of the eyes) bloodshot
(of the hands) stained with blood, as after committing murder
bloody or violent
red revolution
(of wine) made from black grapes and coloured by their skins
denoting the highest degree of urgency in an emergency; used by the police and the army and informally (esp in the phrase red alert )
relating to, supporting, or representing the Republican Party Compare blue
Communist, Socialist, or Soviet
radical, leftist, or revolutionary
a member or supporter of a Communist or Socialist Party or a national of a state having such a government, esp the former Soviet Union
a radical, leftist, or revolutionary
First recorded before 900; Middle English red, Old English rēad; cognate with German rot, Dutch rood, Old Norse raudhr, Latin rūfus, ruber, Greek erythrós; see rubella, rufescent, erythro-
Middle English -rede, Old English -rǣden
The color red is a primary hue found at the end of the spectrum. You might turn red with embarrassment. It also represents financial loss, as in the term "red ink." The word red goes back to before 900, and we can see its roots in the Old English rēad. The idea of red as a signal to stop came in 1849. The color has been associated with rebellion as far back as the 13th Century, and in 1917, the Russian Bolsheviks adopted the color as their symbol. When the movement became the political party of Communism, the members became known as "Reds."
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"The growth of green hydrogen depends on the political momentum," Korsgaard said, urging European Union countries and politicians to push for ambitious implementation of the EU's so-called RED III renewable energy directive.
From Barron's • Nov. 3, 2025
Previous research suggests that improving both the flow of ions across the RED membrane and the efficiency of electron transport would likely increase the amount of electricity captured from osmotic energy.
From Science Daily • Apr. 24, 2024
However, Seb Goldin, chief executive of RED Driver Training, welcomed the default 20mph.
From BBC • Sep. 20, 2023
“Administrators reeled, choking on its noxious reek, as it tore their offices asunder. Cut slips, tardy slips, suspension notices, bad conduct notices, report cards--all were swept away in its churning mist. It was...the RED TIDE.”
From Los Angeles Times • Aug. 16, 2023
And thanks to this message, as well as others sent from Berlin that week, Elizebeth had advance notice that RED was about to start using an Enigma machine.
From "The Woman All Spies Fear" by Amy Butler Greenfield
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
