Penelope is an unlikely 21st century baby name success story. Off the Top 1000 for 25 years, Penelope jumped back on in 2001 and has been heading uphill ever since, propelled by the trend for mythological names, Spanish actress Penelope Cruz, and some high-profile celebrity babies.

Actor Kit Harington, aka the dreamy Jon Snow on Game of Thrones, has given this nickname-name new style and appeal for boys. Actress Jodie Foster used it for her son back in the 2000s, while actor Kit Connor of Heartstopper fame may have introduced it to a wider audience.

Atlas is one of those names that was previously thought too powerful for a baby boy, who would have to be strong enough to carry the world on his shoulders. Now Atlas has joined the pantheon of Greek and Roman god and goddess names in the realm of possibility, along with Mars, Zeus and Apollo.

Thanks to the surprise hit revival of Etta James' song At Last and because of recent interest in vintage style nicknames, Etta has established herself as a possible successor to Emma and Ella. While it is currently in the latter end of the US charts, the smart, snappy name is a rising choice in the UK, where it features in the Top 150.

Lucas is a Top 10 boys' name with a slightly-less-popular almost-identical twin brother, Luke. Like Elijah and Elias, Lucas and Luke come from the same root and have the same meaning and so feel even more popular than they are.

Elsie is a sweet vintage nickname-name turned modern star. After a 30-year hiatus, Elsie started climbing the US popularity list 20 years ago and is still headed for the top.

Eliza is a name with a wonderful combination of streamlined zest and Eliza Doolittle charm and spunk. It's a classic that's popular right now -- but not too popular.

Otto is cool again. Long a quintessential Old Man Name, Otto has been promoted to trending darling of adventurous baby namers.

Clementine is a Nameberry favorite that broke back into the US Top 1000 in 2014 after more than half a century off the list.

Leo is a strong-yet-friendly name that was common among the Romans, used for fourteen popes, and is now at its highest point ever in the US thanks in part to Leonardo "Leo" DiCaprio.

A solid classic with plenty of history, Thomas strikes the balance between strength and gentleness. A favorite in the UK, a staple in France, and Australia, and never absent from the US Top 100, Thomas feels like a safe bet and a name that fits into any era.

Phineas is the English variation of Phinehas, a Hebrew name likely derived from the Egyptian name Pa-nehasi. Pa-nehasi, meaning "the Nubian" can also be translated as "the bronze-colored one." The Egyptians distinguished themselves from their Nubian neighbors through differences in skin tone.

Emma has now been among the top girl names in the United States for several years, claiming the Number 1 crown in 2008 and again from 2015 to 2018 before dropping back to second place.

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.

Matilda is a sweet vintage name that has been gently climbing the popularity list for the past 15 years, after a half-century slumber. The spunky children's book heroine Matilda is one factor in its rise, along with others of its class like Eloise and Caspian.

Ottilie is trending in the UK, where the pronounced T helps the name sound pretty and delicate, rather like Amelie and Elodie. Ottilie is less popular in the US, where many Americans pronounce it as a near-homonym for "oddly".

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.

Beau suggests someone devilishly handsome, with a large measure of southern charm—a nice image to bestow on your boy. Often solely a nickname in the past, it's now standing firmly on its own. Beau has been on the Social Security list non-stop since 1969.

Caroline is a perennial classic, one of the elite group of girls' names that's ALWAYS ranked among the Top 1000 and that's been in the Top 100 since 1994. Elegant yet strong, Caroline calls to mind the Kennedy Camelot years and Princess Caroline of Monaco.

Wyatt has been hot, which is to say cool, for several years now. With its easy Wyatt Earpish cowboy charm, it's relaxed but still highly respectable.