1. (noun)cardinal (Roman Catholic Church) one of a group of more than 100 prominent bishops in the Sacred College who advise the Pope and elect new Popes
2. (noun)cardinal number, cardinal the number of elements in a mathematical set; denotes a quantity but not the order
3. (noun)cardinal, carmine a variablecolor averaging a vivid red
4. (noun)cardinal, cardinal grosbeak, Richmondena Cardinalis, Cardinalis cardinalis, redbird crested thick-billed NorthAmericanfinch having bright red plumage in the male
5. (adj)cardinal, central, fundamental, key, primal serving as an essentialcomponent "a cardinal rule"; "the central cause of the problem"; "an example that was fundamental to the argument"; "computers are fundamental to modern industrial structure"
6. (adj)cardinal being or denoting a numerical quantity but not order "cardinal numbers"
Definition of 'cardinal':
