Classically underused

Bonnie is an adorable nickname name, heading back up the popularity list after a 50-year nap. A Top 100 girls' name throughout the rest of the English-speaking world, Americans are later to jump on the Bonnie bandwagon but now it's trending here too.

The name of the tragic mythological Trojan princess who was given the gift of prophecy by Apollo, but was condemned never to be believed, Cassandra has been used for striking characters in movies and soap operas. Ethereal and delicate, Cassandra was in the Top 70 throughout the 1990s but is now descending in popularity.

In Greek mythology, Daphne was the nymph daughter of Peneus, a river god. Peneus saved Daphne from Apollo’s romantic obsessions by transforming her into a laurel tree. It is from this myth that the plant genus daphne, which contains the laurel species, gets its name.

Diana, the tragic British princess, inspired many fashions, but strangely, not one for her name. For us, Diana is a gorgeous and still-underused choice.

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.

Helena is one of those classic names that just misses making the US Top 1000 girl names for its entire history, falling off for a single year in 1992. Since then it's been drifting lazily up the charts, and makes a perfect choice if you want a name that both fits in and stands out.

Holly ranks just in British Top 50, but it's been out of favor here since the 1970s Era of Nickname Names. Still, the name may be on her way back as a rejuvenated nature pick.

The luminous Ingrid Bergman's appeal was strong enough to lend universal charisma to this classic Scandinavian name, which has been somewhat neglected in the US. Even today, a child named Ingrid would be assumed to be of Scandinavian ancestry, signaling the name has never been fully integrated into the English lexicon the way other European choices from the same era like Danielle or Kathleen have.

Serene Irene, the name of the Greek goddess of peace and one of the most familiar Greek goddess names, was hugely popular in ancient Rome and again in the United States a hundred years ago.

Jacqueline originated as a feminine form of Jacques, the French variation of James, and therefore Jacob. Jacob was ultimately derived from the Hebrew name Ya’aqov, and gets its meaning, "supplanter" from the story of Jacob supplanting his brother Esau as the first-born son in the Bible. Jacqueline was first used in France in the Middle Ages.

This spelling of Jillian is now much more popular than the original, maybe because the G version invites pronunciation problems.

Jocelyn has gotten new life and popularity as a result of the current passion for lyn endings. Though it was a male name in medieval times, now Jocelyn couldn't sound more softly feminine.

Popularized in the 1940s by Lana (born Judy) Turner, today Lana is synonymous with American singer-songwriter Lana Del Rey. Although it has been rising steadily since the early 2000s, Lana still sits in the popularity "sweet spot" – familiar, but not overused. Simple, sleek and seamlessly international, it makes a great choice.

An underused classic that has proved surprisingly unisex over the last few decades, being given to roughly the same number of baby girls and boys in the US from the 1970s to the 2000s. For a girl, Marion has a sturdy old-fashioned charm.

Meredith is a soft, gentle-sounding name with subtle Welsh roots. Although originally a boys’ name , Meredith is used mainly for girls now.

Rebecca is a name representing beauty in the Bible, an Old Testament classic that reached the heights of revived popularity in the seventies but is still a well-used choice. It derives from the Hebrew name Rivkah, from the verb ribbqah, meaning "noose." The biblical Rebecca was the wife of Isaac and the mother of Esau and Jacob. Rebekah was a common spelling of the name in the Bible.

Sabrina, the bewitchingly radiant name of a legendary Celtic goddess, is best known as the heroine of the eponymous film, originally played by Audrey Hepburn, and later as a teenage TV witch; it would make a distinctive alternative to the ultrapopular Samantha. Similar names you might also want to consider include Sabina and Serena.

Susannah is by far the most stylish form of the classic name now that Susan and Suzanne have retired. Susannah has biblical and musical pedigrees, is impervious to trends, and has an irresistible, flowing rhythm. It can be spelled just as properly with or without the final 'h.'

The musical, sylvan Sylvia seems poised to join former friends Frances and Beatrice and Dorothy back in the nursery.

The name of a martyred medieval saint, Valerie has been on the popularity list since its earliest publication in 1880. Though it peaked in the 1960s, remaining in the Top 100 until 1988, it still doesn't sound terminally dated; the association with the word valor gives it a sense of boldness and makes it one of the special group of girl names that mean strong.