Castiel is of Hebrew origin, meaning 'covered by God'. It is derived from the name of an angel in the Bible, who was believed to be one of the seven archangels. The name first gained significant popularity due to its use in popular culture, notably in the television series 'Supernatural', where it is the name of a main character. In recent years, Castiel has been increasingly adopted as a baby boy's name in English-speaking countries.
"Castiel experienced a steady increase in popularity from 2013 to 2016, with a slight dip in 2018 and maintaining at the same level in 2020."