Kaidyn is one of the many spellings of Kaden, a modern American name usually traced to the Irish surname Mac Cadáin, "son of Cadán", a name meaning "little battle"; it also fits the rhyming -aden family led by Aiden, Jayden and Brayden. The y spelling was a 2000s trend. Kaidyn climbed from number 9695 in 2000 to a peak of number 1043 in 2012, just outside the top 1000, and stands at number 2157 in 2025.