crested thick-billed North American finch having bright red plumage in the male
- cardinal grosbeak - richmondena cardinalis - cardinalis cardinalis
a variable color averaging a vivid red
the number of elements in a mathematical set
denotes a quantity but not the order
- cardinal number
(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
being or denoting a numerical quantity but not order
serving as an essential component
"a cardinal rule"
"the central cause of the problem"
"an example that was fundamental to the argument"
"computers are fundamental to modern industrial structure"