- a high ecclesiastic appointed by the pope to the College of Cardinals and ranking above every other ecclesiastic but the pope.
- 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.
- 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.
- 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.
- a spotted, orange nymphalid butterfly with a green underside, Argynnis pandora, found throughout southern Europe and some adjoining regions of Asia and northern Africa.
- a deep, rich red color.
- a woman's short cloak with a hood, originally made of scarlet cloth and popularly worn in the 18th century.
- cardinal number.
- any of the members of the Sacred College, ranking next after the pope, who elect the pope and act as his chief counsellors
- a deep vivid red colour
- See cardinal number
- a crested North American bunting, Richmondena (or Pyrrhuloxia) cardinalis, the male of which has a bright red plumage and the female a brown one
- a fritillary butterfly, Pandoriana pandora, found in meadows of southern Europe
- a woman's hooded shoulder cape worn in the 17th and 18th centuries
- fundamentally important; principal
- of a deep vivid red colour
- of or relating to the signs Aries, Cancer, Libra, and Capricorn
