The terms vibrato and tremolo are sometimes incorrectly used interchangeably, although (in the classical world) they are properly defined as separate effects with vibrato defined as a periodic variation in the pitch (frequency) of a musical note, and tremolo as a fast repetition of the same note (usually a semiquaver) in order to produce the audible ...
The cardinal is easy to spot due to its coloring. It is one of the most popular birds and easily identified by birdwatchers and non-bird-watchers alike. Like the robin, whose plumage also features a distinctive red patch, the cardinal is often associated with Christmas and the winter season.
The cardinal virtues (c.1300) were divided into natural (justice prudence, temperance, fortitude) and theological (faith, hope, charity). The N.Amer. songbird (Cardinalis virginianus) is attested from 1678, so named for its resemblance to the red robes of the cardinals.