The related Lucas and Luke are both hugely popular boy names in the US and internationally, and now Luca has joined them on boys' popularity lists around the world.

Tobias is one of a number of s-ending boys' names that are riding a wave of popularity. With its Old Testament-Dickensian feel, it's a name with a distinguished pedigree.

Otis has real appeal for parents attracted to its catchy O initial and combination of strength and spunk. The appealing hero of the British TV show Sex Education has done much to propel Otis into the forefront of cool names.

Effortlessly stylish with an international feel, Milan re-entered the US charts back in 2013 after a 55 year hiatus. It has been powering up the charts ever since, following in the footsteps of sweet sound-alike Mila, and spotlighted by singer Shakira, who chose it for her son.

Jace may sound like only half a name -- it's usually pronounced like the first half of Jason though some may consider it a spelling-out of the initials J. C. -- but it's a popular choice for baby boys. Jace has been heard on such TV shows as Teen Mom 2 and Duck Dynasty.

Zayn zoomed up the popularity charts thanks to former One Direction member Zayn Malik; it was one of the fastest-rising names of 2016. The name can also be spelled Zain; the feminine version is Zayna or Zaina.

Bram has an unusual measure of character and charm for a one-syllable name; it started as a hipper-than-Abe diminutive of the biblical Abraham, but is also an independent Irish and Dutch name, made famous by Irish-born Dracula creator Bram (nee Abraham) Stoker. Bram is currently Number 16 in the Netherlands; Bram Howard was a character on The West Wing.

This sleek, warm-hued spelling spin on Rowan was chosen by Sharon Stone for one of her three sons back in the 2000s and it has since risen in popularity in the US. While it remains a long way behind its sometimes sound-alike Rowan, it was still given to more than 140 babies in a recent year.

Now that such Old Testament patriarchs as Elijah and Moses fill the playground, Boaz seems downright baby-friendly, having more pizzazz than many of the others, perhaps as a successor to Noah.

Cato conjures up images of ancient Roman statesmen and southern antebellum retainers; it could have revival potential, with its 'O' ending and the current interest in the names of Greek and Roman antiquity.

Lars is a perfect candidate for a cross-cultural passport: it has been heard often enough here to sound familiar and friendly, yet retains the charisma of a charming foreigner.

Especially for parents of Scandinavian descent, Sven is an accessible and attractive name with an appealing mix of strength and swagger. It comes from the ancient Swedish tribe, the Sviars, who gave their name to Svealand, which later morphed into Sweden.

A popular name in the Netherlands that's arguably more attractive than the original, Sem is a Dutch variant of the Biblical Shem who was one of the sons of Noah. Only ever given to a handful of boys in the US, it is currently in the Dutch Top 10 and a familiar option in Belgium and Italy. It might also be used as a short form of Semion or Semyon in Russia.

This Dutch favorite was the name of five Counts of Holland and many notable Renaissance artists, including still life painter Floris van Dijck. It is a variation of Florence, ultimately from the Latin florens, which was historically a unisex name.

Morris is as quiet and comfortable as a Morris chair, and has the same vintage feel. Once a Top 100 name in the early 1900s, Morris fell completely off the roster in 1995, probably due to lingering fallout from his identification with Morris the cat's ("the world's most finicky cat") 9 Lives cat food commercials.

The streamlined Ruben is much more popular than the original Biblical Hebrew version in the US.

Boris is one of the old Russian names being revived by chic Europeans; it hasn't quite made a comeback yet in the U.S., but it does have potential.

A standard form of John in Dutch, Swedish, Norwegian, Danish, Czech, Polish, Slovene, German, and Catalan. Properly pronounced yahn (in most of these languages), most Americans will still equate it with the Brady Bunchesque girls' name Jan, which is now officially extinct.

This short-but-strong name is popular for boys in The Netherlands. While Cass is usually a female name in the U.S., it feels just as right for boys.

Short but substantial Nordic name that travels well -- although it runs the risk of being confused with all the feminine Jen names.