cardinal

American  

[kahr-dn-l] / ˈkɑr dn l /

noun

1. Roman Catholic Church. a high ecclesiastic appointed by the pope to the College of Cardinals and ranking above every other ecclesiastic but the pope.

2. any bird belonging to the genus Cardinalis of the family Cardinalidae (cardinal family), especially the common northern cardinal of North America, the male of which is bright red.

3. any bird of the Americas belonging to the genus Piranga, Chlorothraupis, or Habia, including the scarlet tanager: these three genera were long considered part of the tanager family but are now classified as members of the cardinal family.

4. Also called red-headed cardinal.  any bird belonging to the genus Paroaria of the tanager family (Thraupidae), noted for drab plumage other than conspicuously red head parts: most common in South America, Paroaria species include the prominently crested P. coronata, which has been successfully introduced to Puerto Rico and Hawaii.

5. Also called Mediterranean fritillary.  a spotted, orange nymphalid butterfly with a green underside, Argynnis pandora, found throughout southern Europe and some adjoining regions of Asia and northern Africa.

6. a deep, rich red color.

7. a woman's short cloak with a hood, originally made of scarlet cloth and popularly worn in the 18th century.

8. cardinal number.

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adjective

1. of prime importance; chief; principal.

   of cardinal significance.

2. of the color cardinal.

cardinal British  

/ ˈkɑːdɪnəl /

noun

1. RC Church any of the members of the Sacred College, ranking next after the pope, who elect the pope and act as his chief counsellors

2. Also called: cardinal red.  a deep vivid red colour

3. See cardinal number

4. Also called: cardinal grosbeak.   redbird.  a crested North American bunting, Richmondena (or Pyrrhuloxia ) cardinalis, the male of which has a bright red plumage and the female a brown one

5. a fritillary butterfly, Pandoriana pandora, found in meadows of southern Europe

6. a woman's hooded shoulder cape worn in the 17th and 18th centuries

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adjective

1. (usually prenominal) fundamentally important; principal

   cardinal sin

2. of a deep vivid red colour

3. astrology of or relating to the signs Aries, Cancer, Libra, and Capricorn Compare mutable fixed

Other Word Forms

• cardinally
  adverb
• cardinalship
  noun
• intercardinal
  adjective
• postcardinal
  adjective
• subcardinal
  adjective
• subcardinally
  adverb
• uncardinally
  adverb

Etymology

Origin of cardinal

First recorded before 1150; Middle English, Old English, from Latin cardinālis, equivalent to cardin- (stem of cardō ) “hinge,” hence, something on which other things hinge + -ālis adjective suffix; see -al ¹

Explanation

A cardinal is a bright red songbird, and the word also refers to the bird's crimson color. In Catholicism, a cardinal is a high-ranking bishop. In math, you use cardinal numbers to count. A cardinal rule is one that is central and should not be broken. Okay, that's a lot of definitions. How exactly are they related? In most cases, cardinal means central or essential. It's a cardinal principle that you use it to describe words of behavior like rule or sin. In the Church, cardinals form the central governing body, and in math the cardinal numbers (one, two, three) are the numbers you learn and use first.

Example Sentences

Both the Pentagon and the Vatican denied a report, published in the Free Press last week, that the meeting was tense, with Colby lecturing the cardinal on U.S. military power.

From The Wall Street Journal • Apr. 10, 2026

Another trip in the works is to Spain, with potential events in Madrid, Barcelona and the Canary Islands, a Spanish cardinal said last month.

From Barron's • Feb. 10, 2026

The cardinal sin of “The Last Days” is that it doesn’t choose a storyline.

From Los Angeles Times • Jan. 20, 2026

Before Robby and Al-Hashimi engage in any real ideological tussles, though, she commits the cardinal sin of suggesting they change the trauma center’s nickname to something else.

From Salon • Jan. 8, 2026

But as the weeks rolled on, he experienced firsthand the cardinal principle of American politics in the 1790s: whoever went face-to-face against Washington was destined to lose.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis

Related Words

• overriding