Cassie is a pet form of Cassandra, the Trojan prophetess of Greek legend whose name is of uncertain meaning and usually explained as "shining upon men". It stood on its own for decades and peaked in the 1980s, when it had the easygoing sound of Carrie and Katie. Cassie ranked number 348 in 2000, left the US top 1000 in the 2010s and stands at number 1,280 in 2025.