Illustration of cardinal
- cardinal 3
plural cardinals
1
: a high ecclesiastical official of the Roman Catholic Church who ranks next below the pope and is appointed by him to assist him as a member of the college of cardinals (see college sense 6)
2
: cardinal number
—usually used in plural
3
a
[from its color, resembling that of the cardinal's robes]
: a crested finch (Cardinalis cardinalis of the family Cardinalidae) of the eastern U.S. and adjacent Canada, the southwestern U.S., and Mexico to Belize which has a black face and heavy red bill in both sexes and is nearly completely red in the male
b
: any of several red-headed passerine birds (genus Paroaria of the family Thraupidae) of South America and the West Indies that are grayish to blackish above with white underparts
1
: of basic importance
a cardinal principle
2
: very serious or grave
a cardinal sin
cardinally
adverb
Did you know?
Mathematics, religion, ornithology—everything seems to hinge on cardinal. As a noun, cardinal has important uses in all three of the aforementioned realms of human inquiry; as an adjective cardinal describes things of basic or main importance, suggesting that outcomes turn or depend on them. Both adjective and noun trace back to the Latin adjective cardinalis, meaning “serving as a hinge,” and further to the noun cardo, meaning “hinge.” Since the 12th century, cardinal has been used as a noun referring to a fundamentally important clergyman of the Roman Catholic Church, ranking only below the pope. (The clergyman's red robes gave the familiar North American songbird its name.) By the 1300s cardinal was also being used as the adjective we know today, to describe abstract things such as principles or rules (as opposed to, say, red wheelbarrows) upon which so much depends.
Synonyms
Adjective
Examples of cardinal in a Sentence
Noun
The Pope appointed two new cardinals this year.
Adjective
the cardinal principles of news reporting
My cardinal rule is to always be honest.
Recent Examples on the Web
Benjamin Royer, Los Angeles Times, 19 Jan. 2025
Listen to this article Ahead of his permanent move to Washington, D.C., San Diego’s first-ever cardinal wanted thousands of people who attended Saturday’s 13th annual Walk for Life to remember one thing: honor human life.
—Tammy Murga, San Diego Union-Tribune, 18 Jan. 2025
Kristen Waggoner, Newsweek, 22 Jan. 2025
Even the city’s fire chief, Kristin Crowley, has come under scrutiny, breaking one of the cardinal rules in this country—that firefighters can never be criticized during a disaster.
—Jay Caspian Kang, The New Yorker, 16 Jan. 2025
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Noun
Two years later, in likely her final season in cardinal and gold, Marshall is the first to tell anyone that the credit goes to Burns for her success — her coach who takes the time to pull her aside before or after practice to watch film or to give her notes on how to get better.
—Benjamin Royer, Los Angeles Times, 19 Jan. 2025
Listen to this article Ahead of his permanent move to Washington, D.C., San Diego’s first-ever cardinal wanted thousands of people who attended Saturday’s 13th annual Walk for Life to remember one thing: honor human life.
—Tammy Murga, San Diego Union-Tribune, 18 Jan. 2025
Adjective
According to The Knot, one of the cardinal rules of being a good wedding guest is to avoid actions that draw focus away from the couple.
—Kristen Waggoner, Newsweek, 22 Jan. 2025
Even the city’s fire chief, Kristin Crowley, has come under scrutiny, breaking one of the cardinal rules in this country—that firefighters can never be criticized during a disaster.
—Jay Caspian Kang, The New Yorker, 16 Jan. 2025
See all Example Sentences for cardinal
Articles Related to cardinal
Dictionary Entries Near cardinal
Cite this Entry
“Cardinal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cardinal. Accessed 12 Feb. 2025.
Copy CitationKids Definition
cardinal
1 of 2 noun
car·di·nal
ˈkärd-nəl 
-ᵊn-əl
1
: a high official of the Roman Catholic Church ranking next below the pope
2
3
: a North American finch of which the male is bright red with a black face and a pointed bunch of feathers on its head
cardinal
2 of 2 adjective1
: chief entry 1 sense 2, primary
a cardinal rule
2
: very serious
a cardinal sin
Etymology
Noun
Middle English cardinal "high church official," from Latin cardinalis (same meaning), from cardinalis (adjective) "principal, most important, of a hinge," from cardo "hinge"
Word Origin
Our word cardinal can be traced back to the Latin adjective cardinalis, which at first meant "serving as a hinge." The root of this word is the noun cardo, meaning "hinge." Since a hinge is the device on which a door turns, the noun cardo also came to be used for "something on which a development turns or depends," or in other words, "something very important." Following this, the adjective took on the meaning "very important, chief, principal." Later the Roman Catholic Church applied this adjective in referring to principal churches and priests. By the late Middle Ages cardinalis had come to be used for "a clergyman of the highest rank, next to the pope." When borrowed into English, cardinalis became cardinal. Then other senses of the word developed. A cardinal's robes are a deep red color, and this color influenced the naming of a type of bird whose color was like that of a cardinal's robes.
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