When a thing is named, its name seems to capture something of its inner nature. The name – cardinal – of the bird now singing its monotonous song in my garden embodies its very essence.
But that sense of inner meaning is an illusion, arising only after the arbitrary label has been attached. Unlike the words splash, bonk, and fizz, which actually mean something in that they are directly connected to what they stand for, the word cardinal comes from the Latin cardo, meaning “hinge,” “pivot,” or “turning point.” It has nothing to do with the name of the bird, except for a simple-minded connection humans made when they were transplanted from the Old World to the New.
It would be reasonable to presume that those high-ranking, privileged, red-robed, red-capped officials of the Catholic church, the Cardinals of Rome, who have been around for not even two thousand years, were named after the gloriously red birds which have existed for millions of years before them. The case, however, is the reverse. In English, the birds were named after the bishops.
The Latin word cardo was likely first applied to the Roman bishops of the 5th or 6th century, in its adjectival form cardinālis (hinge-like), because the functions of the Church turned on their authority. The scarlet color of their robes and mitres was chosen to symbolize the blood the bishops would be willing to shed for their faith. The high status of the bishops has been retained in our use of the word cardinal to mean “important,” “chief,” “principal,” or “main” – as in “the cardinal points of the compass,” “cardinal numbers,” “a cardinal sin,” “a cardinal virtue,” and “a cardinal rule.”
When colonists first arrived on North American shores, bringing their European culture with them, they called the birds cardinals because their red crests reminded them of the caps of the Cardinals of Rome. Humans had already bestowed on this bird a number of different names: do-tsu-wa (Cherokee), ma'evé'késo (Cheyenne), pebduta (Dakota), misko-bineshiinh (Ojibwe). But the colonists were ignorant of those names. So for them, and for us, the bird is a cardinal, in all its cardinalness.