Jack began in medieval England as a pet form of John, by way of Jankin, and means "God is gracious"; it became so common that "every man Jack" came to mean everyone. Jack Kennedy and Jack Nicholson stand for its American side, and it is the hero's name in countless fairy tales. Jack has been in the top 100 throughout the SSA records since 2000 and ranks fifteenth in 2025, close to its peak of eleventh in 2021.