Once a macho biker name, Harley is now showing its softer side, given to over seven hundred girls last year, which is almost twice the number of boy Harleys. In the UK, Harley is still much more male--it's currently Number 55 there.
Along with Harper and Hadley, we think it will climb even further. In England it's associated with Harley Street, home to some of London's most prominent medical specialists.
Harley came over to the girls' side in 1991, long after being the name of the Joker's female assistant in Batman, Harley Quinn, 'born' Harleen Quinsel, and then as a character, Harley Cooper, who was introduced on the soap The Guiding Light in 1987--that Harley was named after her father's favorite motorcycle..