Caspian is a place name rather than a word: it means "from the Caspian Sea", the vast inland sea between Europe and Asia, named after the ancient Caspi people who lived on its shores. C. S. Lewis made it a first name with Prince Caspian in his Chronicles of Narnia, and the 2008 film brought it to a new generation. Caspian entered the US top 1000 in 2017 and has risen every year since, from number 861 to number 491 in 2025, its highest rank yet.