Sadie started as a nickname for Sarah, but their images couldn't be more disparate. Where Sarah is serious and sweet, Sadie is full of sass and fun.

Sophie is the French form of the Greek Sophia, for which it is also commonly used as a nickname. Given Sophia's long standing among the Top 10 girl names in the US, Sophie may feel more popular than it actually is.

Stella is a name with star quality and sparkle, that manages to sound both ethereal and earthy. Celestial but not otherworldly, it lands somewhere between the popular Ella and bold Seraphina.

Simon is pure and simple (not in the nursery rhyme sense), and an appealingly genuine Old and New Testament name that's not overused. These factors make Simon a stylish yet classic choice.

Samuel has been so popular for so long that it's hard to believe it's still climbing, at its highest point since the 1890s.

Sebastian is an ancient martyr's name turned literary, and Little Mermaid hero—think Sebastian the Crab—that's more popular than ever, as a classic-yet-unconventional compatriot for fellow British favorites T Theodore and Oliver.

Solomon, a name that evokes wisdom and peace, is an Old Testament name that, along with other patriarchal classics, is finally beginning to shed its long white beard and step from the pages of the Old Testament into modern nurseries.

Sage is an evocatively fragrant herbal name that also connotes wisdom, giving it a double advantage. It entered the Top 1000 at about the same time for both genders in the early 1990s, but it has pulled ahead for the girls. Toni Collette named her daughter Sage Florence.

Spencer is a name that has everything: it's both distinguished sounding and accessible, dignified but Spencer Tracy-like friendly. Picked by several celebrities (a couple of times even for a girl), adding up to an enthusiastically recommended choice.

The name is derived from the term commonly used in the Book of Psalms, which has a many Hebrew scholars in confusion over its meaning. Given its context in the Bible, Selah is likely to mean "to praise" or "pause and reflect upon what has just been said." Lauryn Hill used this name for her daughter. It is the last word in Anita Diamant's novel The Red Tent.

The long-neglected name of Adam and Eve's third son after Cain and Abel, Seth is appreciated for its gentle, understated presence -- and strong middle-name potential. It reached a high of Number 63 in the year 2000.

Santiago is a spirited Spanish name with great crossover potential. It's a place-name (a city in Chile), a surname, and the name of the patron saint of Spain.

Soraya is a Persian name made famous in the Western world by the one-time empress of Iran, who settled in Europe, primarily in France. Soraya is derived from Thurayya, the Arabic name of the Pleiades, a group of stars in the constellation Taurus.

A soft and interesting Hebrew name long popular in France, where it has ranked in the Top 400 since 1986 (as Salomé). Ex-ER star Alex Kingston named her daughter Salome Violetta.

Sally is a cheerful, fresh-faced girl-next-door name that was originally a nickname for Sarah, but has long been used independently. Sally was popular in the eighteenth century and then again from the 1920s to the 1960s--it was just outside the Top 50 around 1940. Though it hasn't been heard as a baby name for decades, we can see Sally bouncing back, especially after her exposure as young Ms. Draper on Mad Men--the Nameberries rank it at Number 621, and it's a Top 100 name in Sweden.

Popular throughout Northern and Eastern Europe, particularly in countries like Sweden, Norway, Russia, and Germany, Sonja has a rich cultural heritage. The name gained international recognition through figures like Sonja Henie, the Norwegian Olympic figure skating champion.

Popular Russian name, familiar here via author Svetlana Stalin, the dictator's daughter.

Scheherazade -- or Sheherazade --is a legendary Persian queen immortalized as the narrator of all one thousand stories in the One Thousand and One Nights. Her story is even more remarkable than the tales she tells.

Seneca was both a Roman philosopher-statesman and is a Native American Iroquois tribe. Occasionally used for both girls and boys, Seneca is now a Hunger Games character.

With related choices such as Lark and Phoenix gaining popularity, why not Sparrow? Though it's usually thought of as a female name, Nicole Richie and Joel Madden chose it for their son.