Boy names II.

Long an extremely popular name in Spain, Iker (usually pronounced EE-kuhr in the English speaking world) is the rare Basque name that's starting to make it big in the States also, thanks to soccer player Iker Casillas. Indeed, it's been one of the fastest growing boys' names of the decade.

Jackson is one of those names that's much more popular than you think, coming in near the top of our annual Playground Analysis, which ranks names by grouping all their spellings together. Last year, nearly 17,000 baby boys were named Jackson -- along Jaxon, Jaxson, Jaxxon, Jaxen, Jaxyn, Jaxsen, and Jaxsyn -- which counted together makes it the Number 3 boys' name.

A Hispanic classic that has lost some momentum in recent years. It could be misunderstood by some as Jamie -- which is how it's pronounced on Game of Thrones.

After cracking the US Top 200 in the early 2000s, fueled by Jacob's rise, this name has been losing steam in recent years. But Jakob is the top form of the name in many other countries, cultures, and languages, ranking highly in Germany, Norway, Austria, Iceland, and Slovenia. Jakub is the Polish variation.

This is a strong new James varietal, sometimes shared by girls. An original way to honor Grandpa Jim, Jameson is swiftly moving up the charts, entering the Top 100 for the first time ever in 2017. Jameson is one of the hottest boy names starting with J, still the most popular first initial for boys' names. One small caveat: Jameson is also a brand of whiskey.

Jason, the Number 3 name for the entire decade of the 1970s -- thus the title of our original baby-naming book, Beyond Jennifer & Jason -- is more likely to be dad's name now than baby's, but it's still a widely used name.

Jasper originated as a variation of the Latin Gaspar, which ultimately derived from the Persian word ganzabara, meaning "bringer of treasure." As a given name, Jasper’s etymology is unrelated to that of the gemstone, which comes from a Semitic word meaning "speckled stone." Jasper is the usual English form for one of the Three Wise Men who brought gifts to the infant Christ according to medieval tradition and appears in the Bible as a reference to the stone itself in Revelations 4:3.

Streamlined version of the classic boys' names, sometimes a short form of Jonathan, which is in fact an entirely different name from John attached to a different Biblical personage. Jon feels more modern than the traditional John, but some may find it an overly slight variation on an already slim name. Jon Snow is a popular character on HBO's Game of Thrones.

Jonah, the name of the Old Testament prophet who was swallowed by the whale, only to emerge unharmed three days later, is increasingly appreciated by parents looking for a biblical name less common than Jacob or Joshua, yet not too obscure. Plus, Jonah comes with a ready-made nursery-decorating motif.

Kai is an internationally flexible name with many possible origins and meanings, growing in popularity in the US and a diverse range of European countries.

An evocative name brought from Hawaii to the mainland by Keanu Reeves, who was born in Beirut to a part-Hawaiian, part-Chinese father. It moved into the Top 1000 for the first time in over a decade in 2016. Keanu ranks among

Kellan Lutz is the attractive young actor who plays Emmett Cullen in the Twilight series.

Long popular in Ireland and England, Kieran, the name of Ireland's first-born saint and twenty-five other saints, has been building its U.S. fan base thanks to its strong and attractive sound, and its fashionable Irish brogue. While Ciaran is the more authentic Irish spelling, Kieran is more popular this side of the Atlantic.

Lennox is an aristocratic and powerful Scottish surname name made truly special by that final x. The worldwide fame of British boxer--World and Olympic champion--Lennox Claudius Lewis brought the name into the spotlight as a first name, while as a last it's tied to Eurythmics singer Annie L.

Leonard is the name of several saints, including one who is the patron saint of childhood, and another medieval saint who's the patron of prisoners--known for freeing prisoners he deemed worthy of God. Popular from 1900 to 1930, Leonard is perhaps more notable for those who dropped the name when they entered show biz than those who kept it: former Leonards include Roy Rogers and Tony Randall. Two musical Leonards did keep their names though--composer-conductor Leonard Bernstein and poet-singer Leonard Cohen. Leonard Woolf was the husband and publisher of great English novellist Virginia Woolf. These days, modern parents tend to prefer Leo or the romantic Italian Leonardo, especially since Leonard does not get pronounced with the trendy "Leo" sound.

Levin, known in the U.S. mostly as a surname, is a Top 100 boys' name in Germany. There have been saints with variations of this name, whose meaning relates to love.

Kate and William shocked the world when they announced that they'd named their third child Louis -- Prince Louis Arthur Charles, to be more precise. But we've been predicting a comeback for this classic name for a long time.

Long gone to the girls.

Magnus is a Latin name, literally meaning "greatest," that has a Scandinavian feel. It dates back to Charlemagne being called Carolus Magnus, or Charles the Great. Norwegian king Magnus I, named after Charlemagne, introduced it to his culture, and thus Magnus was the name of six early kings of Norway and four of Sweden. It is still a highly popular name in Denmark and Norway.

An Old Testament name with a Gaelic lilt, Malachi entered the list in 1987.