Aeron was possibly a minor Celtic god of war, and is definitely a river in modern-day Wales.

Aeron

Alis

Aderyn

Awstin

Very popular in Wales, this perfectly nice name's only problem is its similarity to the dated Beth Ann. 

Bethan

Unusual floral name which would be perfect for a spring baby girl, if you can pronounce the Welsh double L correctly. It's a tricky sound for non-native Welsh speakers, kind of halfway between an H and an L.

Briallen

One of the loveliest of the <a href="https://nameberry.com/baby-names/172/welsh-names">Welsh names</a>, striking the perfect balance between being familiar and unusual. In Wales, the female spelling is always Bronwen, but Americans usually see a "y" as adding femininity.

Bronwyn

Bryn is an up-and-coming gentle, yet substantial, Welsh name that would also be effective in the middle spot. In Wales it's a traditional boys' name, but it's far more popular for girls now in the US.
 Bryn entered the U.S. girls' popularity list in 1999 but is outranked by the Brynn spelling. Reality star Bethenny Frankel named her daughter Bryn in 2010.
 Trivia tidbit: Bryn Mawr college was the first institute of higher learning to offer graduate degrees to women.

Bryn

One of the cute diminutives that's in vogue in Wales... or could be an alternative spelling of Kaydie.

Cadi

Common in Wales, this name was introduced to America when Welsh-born Catherine Zeta-Jones and husband Michael Douglas chose it for their daughter in 2003. It didn't come into use in Wales until the late nineteenth century. It's currently Number 367 in England and Wales.
 Carys is one of that sweet group of girls' names with a loving meaning, and this has a subliminal link to the word 'caress.'
 Cerys is also heard in Wales.

Carys

The sweet and simple Welsh form of Katherine, long popular in Wales but dropping down the popularity charts now. As a German name, it's a short form of Katharina.

Catrin

In Welsh, Ceri is traditionally a male name but can also be used for girls. It's a short form of Ceridwen too, the name of the Welsh goddess of poetry.

Ceri

Crystin

Extremely common in Wales and England, Dafydd would likely leave some non-Welsh speakers confused at first. But we love the soft, lispy quality this variation offers.

Dafydd

Dylan still feels poetic and romantic after years of popularity. It still ranks highly on the charts, among the top <a href="https://nameberry.com/search/boys-names/d">boy names starting with D</a>, so if you choose it, be aware that yours may not be the only Dylan in his class. 
 <br/
Dylan was derived of the Welsh components dy and llanw, meaning "sea." In Welsh mythology, Dylan was a legendary sea god who prompted all the waters of Britain and Ireland to weep when he died. The name came to prominence via the great Welsh poet Dylan Thomas, whose name Bob Dylan adopted in tribute.
 >Several celebrities have sons named Dylan, including Welsh-born Catherine Zeta Jones and Michael Douglas, Kenneth 'Babyface' Edmonds and Nadia Comaneci.
 The name Dylan was given to about 500 baby girls last year, but 6700 baby boys so it doesn't quite qualify as unisex. 
 Dillon is another popular spelling, though the Dillon spelling is used only about 5 percent of the time.

Dylan

Elain

Evan has a mellow nice-guy image that has kept it popular, while it has been widely used in Wales since the nineteenth century. And interestingly—and surprisingly—enough, Evan charts highly for boys in France.
 Evan was derived from Iefan, a Welsh version of John. John is ultimately a derivative of the Hebrew name Yochanan, comprised of the elements yo, meaning "God" and chanan, "to be gracious." Evan is actually a Hebrew word itself, meaning "rock."
 
Jenny McCarthy has a son named Evan, and some other modern associations are former Senator Evan Bayh, novelist Evan Hunter, and the movie Evan Almighty. It is also sometimes used for girls, as in actress Evan Rachel Wood.

Evan

Glenda

Grigor

While Gwen may have originated as a short form of Gwendolen and Gwendolyn, these days it frequently stands on its own. Rocker Gwen Stefani has given it a shot of cool, and parents are choosing it as a standalone more and more often—Gwen hopped back onto the US Top 1000 in 2013 after an absence of over 30 years. Gwen could also be short for Guinevere.

Gwen

One spelling variation that's more popular than the original, this somewhat old-fashioned name might be in honor of poet Gwendolyn Brooks, the first African-American to win a Pulitzer prize for poetry, or may be a way to get to the modern short form Gwen.
 In the Oscar Wilde play, the character's name is spelled the traditional Welsh way, Gwendolen, as it was for one of the principal characters in George Eliot's Daniel Deronda, and Gwendolen was also Merlin's wife in Arthurian legend.

Gwendolyn

Because of Gwyneth Paltrow, this has almost become a one-person name, but not in the prohibitive there's-only-one-Oprah sense. Also seen as Gwenyth and Gweneth, this mellifluous appellation is definitely becoming more and more appreciated by American parents-- enough to land it on this year's Top 1000.
 Gwyneth is an Anglicized form of Gwynedd, the name of an ancient Welsh kingdom. Gwyneth Jones is an acclaimed Welsh Wagnerian soprano.

Gwyneth

Iago, the villain of Shakespeare's Othello, was so treacherously evil that his name has hardly ever been heard offstage. Try the much-more-benign Inigo.

Iago

This rare sixth-century saint's name has a modern, merry feel. 

Mabyn

Designer (as in Marc Jacobs) form of Mark. An international classic, but long falling in popularity as a boys' name.


Marc

Megan originally evolved from Meg, which itself derived as a nickname for Margaret. Margaret ultimately comes from the Greek word margarites, meaning "pearl." Megan is no longer a common nickname for Margaret—it is most often used as a full name. Other spellings include Meghan, Meagan, Megyn, and Meaghan.
 
One of the most popular <a href="https://nameberry.com/baby-names/172/welsh-names">Welsh names</a> ever in the US—it was Number 10 in the 1990s—Megan is still widely used today, but waning. It fell to its lowest ranking in 50 years in 2017. Actress Megan Fox has upped its glam factor. We've yet to see how the popularity of the new Duchess of Sussex, Meghan Markle, affects all the spellings of her name.

Megan

Meredith is a soft, gentle-sounding name with subtle Welsh roots. Although originally a <a href="https://nameberry.com/boys-names">boys’ name</a>
, Meredith is used mainly for girls now.
 Meredith's highest point of popularity for girls in the U.S. was in the late seventies and into the eighties, when it ranked as high as Number 140.
 Meredith, when said with the American and English pronunciation, offers the delightful "Merry/Merri" as a nickname. Be aware, however, that the correct Welsh pronunciation has the emphasis on the second syllable (muh-RED-ith), making "Reddy" a more suitable nickname.

Meredith

Morgan has long been a traditional Welsh male name, a variant of the Old Welsh name Morcant, from the Welsh elements mor, meaning "sea" and cant, "circle." The female Morgan is unrelated to the male version—it is a name from Arthurian legend created for Morgan le Fay, King Arthur's half-sister and famed sorceress. Her name comes from Morgen, an Old Welsh name meaning "sea-born," and is related to the Irish name Muirgen. 
 
In this country, Morgan is now used more for girls than boys, though considerably lower than its Top 25 status in the 1990's. And although it's been veering south for both sexes, we still find Morgan a sophisticated choice. 
 
Actress Morgan Fairchild—who had an influence on the name's popularity for girls—was born Patsy.

Morgan

Macsen

Short but energetic and substantial, Nia has special meaning for African-American parents, as it's one of the days of Kwanza. Nia also benefits by its similarity to (yet differentness from) the megapopular Mia.
 Current bearers include actresses Long and Vardalos (born Antonia), and popular television show Dance Moms star Nia Frazier.

Owen, a resonant Celtic name, has ranked among the Top 100 boys' names in the US for 20 years and is now at its highest point ever.
 
Why do so many parents love Owen? It's a classic with a genuine history, yet it's right in step with the modern trend for two-syllable, n-ending boys' names. Owen-like choices with less tradition behind them include Logan, Bowen, and Rowan.
 Owen is derived from two names—the Welsh Owain and the Celtic Eoghan. Each are connected to Eugene, which ultimately came from the Greek word eugenes, comprised of the elements eu, meaning good, and genes, "born." 
 
Owen became a Welsh patronymic surname during the Renaissance. The legendary St. Owen was a Benedictine monk who was a follower of St. Chad.
 
In Ireland, Owen may be spelled Eoin, as in Irish writer Eoin Colfer, and Eoghan. Other similar names include the Scottish Ewan or Euan and the French Ouen.
 
Owen's popularity now extends beyond English-speaking countries to France, Belgium, and the Netherlands.

Owen

This is the second most common boys' version of this attractive name, after the Welsh original Rhys. Reese takes the lead on the girls' side. thanks to the famous Ms. Witherspoon.

Reece

Most of us had never heard this lovely Welsh name with links to the moon until we heard the 1976 smash hit Fleetwood Mac song of that name, with lyrics by Stevie Nicks. That same year it popped onto the U.S. Top 1000 at Number 593. 
 After giving his four boys extreme rebel names, director Robert Rodriguez bestowed this sweet name on his first daughter.
 According to Celtic legend, Rhiannon's birds sang more sweetly than any others; she herself was known for being forthright and witty.
 Rihanna looks similar but is unrelated.

Rhiannon

The aristocratic--if not haughty--Roderick was nevertheless consistently in the Top 1000, reaching as high as Number 221 in 1967, when it was not uncommon to run into a Rod or a Roddy. It's at a low point right now, but we can envision it being revived as a neglected, dignified grandpa name, perhaps when Rod is no longer a potentially embarrassing nickname..
 Roderick has lots of literary history, including the novels Roderick Random by Tobias Smollett and Roderick Hudson by Henry James, and Roderick Usher is the main character in the Edgar Allan Poe short story "The Fall of the House of Usher." Roderick, of course, is the full name of Rod Stewart, and TV personality Rosie Pope called her son James Roderick.
 <br/We have to admit that the Spanish version, Rodrigo, has a lot more verve, as does the Irish Rory.

Roderick

Siana

The Welsh form of Steven feels lighter and fresher than the well-trodden English versions.

Steffan

Tailored Tegan comes from a Welsh saint's name. Teagan is just a little bit different, from an Irish surname. The ea spelling is much more popular.
 Musicians and twin sisters Tegan & Sara helped popularize the name, as did a character in Doctor Who.

Tegan

Trevor, a British standard, took a long time to cross the Atlantic, but finally began its rise here in the 1980s. It is now a thoroughly naturalized citizen, though it still retains a touch of Anglo class. 

Trevor

Tristan -- known through medieval legend and Wagnerian opera -- has a slightly wistful, touching air. This, combined with the name's popular "an" ending, makes Tristan very appealing to parents seeking a more original alternative to Christian.
 One influence was the character Tristan Ludlow played by Brad Pitt in the 1994 movie Legends of the Fall, based on a Jim Harrison novel.
 Tristan is a dragon-slaying hero of Celtic legend, whose story was incorporated into Malory's Le Morte d'Arthur, in which Tristan is one of the Knights of the Round Table, consumed by his doomed love affair with Queen Isolde. Wagner set the story to music in his opera Tristan und Isolde.
 Tristan and its alternate form Tristram have been found in later lit as well. Tristram Shandy is a famous early comic novel by Laurence Sterne (in which the hero's father calls Tristram the worst name in the universe); Tristan is a major character in James Herriott's All Creatures Great and Small, and there is an eponymous novella by Thomas Mann.
 Particularly popular in Canada, Tristan was chosen for their sons by Travis Tritt, Wayne Gretzky, Natasha Henstridge and, most recently, by Elsa Pataky and Chris Hemsworth. Basketball player Tristan Thompson hails from Canada.
 Other variants of Tristan include Tristen, Tristin, Triston and Tristian.

Tristan

One of the few remaining unrestored vintage gems, with a choice of two winning nicknames--the girlish Winnie and the tomboyish Freddie--as well as the slight stretch Freda. Winifred, the name of a legendary Welsh saint, was a Top 200 name into the mid-1920's.
 Winifred was one of the Forsytes in The Forsyte Saga, Winifred Foster was the heroine of Tuck Everlasting, and another appeared in Joss Wheden's Angel; in Once Upon a Mattress, Princess Winnifred (two n's) sings the song 'A Girl Named Fred'. The Disney folks seem to have been fond of the name--they used it in Jungle Book, Mary Poppins and Hocus Pocus. 
 Actress Jacqueline Bisset was born a Winifred and notable Winnies include Mrs. Mandela and the young girlfriend on The Wonder Years.

Winifred

Wynne

frauleinawesome's list "Awesome Welsh Names" of 41 great name ideas: Aeron - Wynne!