Girls

Heidi became known—and popular—via the 1880 eponymous children's classic by Swiss writer Johanna Spyri and, despite decades of American Heidis of all sizes, shapes, and personalities, the name seems permanently tethered to that spunky little girl on the Alpine mountaintop in the book and Shirley Temple movie.

Iris has so much going for it. It's a fashionable flower name. It's a mythological name, from the Greek goddess of the rainbow. And it's a classic name, always ranking in the girls' Top 1000 but now at its highest point ever.

Isla is a hit name throughout the English-speaking world but hasn't found the same popularity in other western countries, perhaps because its spelling and pronunciation don't make sense for those whose native language is not English. Think island without the final two letters.

Louisa, a quaint vintage name, is an example of the idea that these days, old-style girls’ names are more fashionable when they end with an a rather than with an e, as in Julie/Julia, Diane/Diana. So for the next generation, Louisa may rise again, especially with the growing popularity of other Lou/Lu-starting names, like Lucy and Luna. Louisa reentered the US Top 1000 in 2014 after a 45 year absence.

Scarlett Johansson is doing more for this sparky southern name than Scarlett O'Hara ever did. Since the turn of the 21st century, Scarlett has gone from an obscure literary name to one of the most popular girls' names starting with S, right after longtime favorites Sophia and Sofia.

Zoe is one of those surprising names that has been on the Top 1000 nearly every year since 1880, but it's only since the turn of this century that it's ranked in the Top 100.