cardinal

The word “cardinal” means of central or fundamental importance. In plain terms, something of central importance, a deep red color, a high-ranking Catholic official, or a red North American songbird.

“Cardinal” is pronounced KAHD-nuhl (/ˈkɑɹd(ɪ)nəl/ in IPA).

Here is “cardinal” used in a sentence: “Honesty is a cardinal rule in this office.”

Depending on how it is used, “cardinal” can be an adjective and a noun.

The word “cardinal” comes from Latin. From Latin cardinalis, "pertaining to a hinge," from cardo, "hinge" — something a cardinal rule or point everything else "turns" on.

“Cardinal” is a fairly common word in modern English.

“Cardinal” has 4 distinct senses listed in this dictionary. The most common is: of central or fundamental importance.

Drawing on the "fundamental" sense of cardinal, cardinal numbers count quantity: one, two, three. Ordinal numbers show position or order: first, second, third. Cardinals tell how many; ordinals tell in what order.

The North American songbird is named for the male's bright red feathers, which resemble the deep red robes worn by a cardinal of the Catholic Church. The color, the church official, and the bird are all linked through that shade of red.

These phrases use the adjective sense of cardinal, meaning of central or fundamental importance. A cardinal rule is a most important, unbreakable rule, and a cardinal sin is a most serious fault or error.

The cardinal directions are the four main points of the compass: north, south, east, and west. The term uses the "fundamental importance" sense of cardinal, since these are the principal reference directions.