Personal favorites during teenage years.

Killian – aka Cillian – is a spirited yet resonant Gaelic name that was borne by several Irish saints and could make a distinctive replacement for the dated Kelly. Kylian is another spelling that's gaining traction, thanks to French soccer star Kylian Mbappé. Possible downsides: an unsavory first syllable and a connection to the trendy brew.

Striking and accessible choice.

Knox is an old Scottish surname that Brad Pitt (whose great-great-grandfather was named Hal Knox Hillhouse) and Angelina Jolie took out of the back cupboard, dusted off, and elevated to coolness--to the point where it entered the popular baby names list in 2009. Knox now ranks among the most influential celebrity baby names.

A new-style name based on Kyle and a cousin of Dylan, in spelling if not sound or image.

This relatively new name appears to have been created by adding the trendy -en suffix to Kyle. Though it lacks a long name history, Kylen has been rising lately, first entering the US Top 1000 in 2014.

An update of Tyson for parents who prefer the Ky nickname to Ty. It was the middle name of a character on Heroes.

Lachlan is as Scottish as haggis and tartan plaid kilts—a favorite used throughout England, Scotland, Australia, and New Zealand—and just beginning to be noticed in the US: it reached the Top 1000 for the first time in 2013. An ancient name, Lachlan was originally used to describe the Viking invaders of Scotland, those from the land of the lochs.

Saint Eulalia was born in Spain and is the patron saint of Barcelona, so her name and its derivatives are popular throughout the land — especially in her native Catalonia.

Not quite a nature name and not quite a surname — whatever Laken is or isn't, we know it's definitely a name to watch.

One of those names that's suddenly on the map because of a celebrity's influence, Leighton Meester of the TV show Gossip Girl. She pronounces it LAY-ton but some will intuitively say LEE-ton.

Lincoln cracked the Top 50 for boys' names for the first time in 2016, more than 150 years after the death of its most famous bearer. This is especially remarkable because, as crazy as it seems now, Lincoln was deeply out of fashion as recently as the late 90s, consistently hovering near the bottom of the Top 1000.

Groovy Mod Squad name that still sounds retro cool.

Llewellyn/Llywelyn is a common patriotic first name in Wales, with its distinctive Welsh double LL's; in the U.S. Llewellyn would make a daring choice, though with the chance that some might find the ellen sound slightly feminine.

Lochlan and Lachlan are running neck and neck and both rising into the Top 1000. Which spelling you use is purely a matter of taste.

A versatile classic, Lucy is both sweet and solid, a saint's name, and the heroine of several great novels. First fashionable in England and Wales, Lucy is now a popular choice in the US, The Netherlands, and New Zealand.

Maddox, a previously obscure Welsh family name with a powerfully masculine image, suddenly came into the spotlight when Angelina Jolie chose it for her son in 2003. By the following year it was in the middle of the Top 1000, and it has risen since.

Sophisticated and sweet, delicate but substantial, Madeleine is the classic French variation of Magdalene.