Declan is the Anglicized form of the Irish name Deaglán. St. Declan was one of the first missionaries to bring Christianity to Ireland, preceding St. Patrick. Originally from Wales, he founded the monastery of Ardmore in Ireland.

A favorite in England and Wales, Darcy is a unisex option with delicacy, grace, and strength. Associated with classic literary and courtesy thanks to Jane Austen's hero, Mr. Darcy, and Bridget Jones's Mark Darcy, its image was partly transformed by English ballerina Darcey Bussell, who helped popularize it for girls.

Delaney has been a popular surname-style choice since 90s, when it joined other Irish surnames such as Cassidy, Kennedy, and Mallory on the US Charts. Buoyant, bright, and cheerful, it ranks in the US Top 250 and is given to nearly 1300 babies every year.

The ultimate Jane Austen hero name, Darcy makes a handsome, surname style choice. Predominantly used for girls in England and Wales, across the pond in Australia, it is a stylish Top 100 name for boys. In the US meanwhile, it does lean feminine, however, 30 boys were given the name in a recent year, suggesting it is on the up across the board.

Once a common boy name in Ireland, the dynamic Darby now has a definite unisex feel. A bit like a mash up between Darcy and Ruby, it appeared in the US Top 1000 in the 90s, peaking in 1995 when it reached #499. It's likely this sudden interest in Darby was owing to the 90s book and film, The Pelican Brief, starring Julia Roberts as a law student called Darby.

Though Dara was an (extremely wise) male figure in the Bible, this name feels mostly feminine to modern Americans. The Irish Gaelic version, Darragh, is well-used in contemporary times for boys.

Darren and wife Sharon shop for fifties memorabilia on eBay. The Connecticut place-name Darien might offer an update.

A laid-back cowboy name which feels both cool and gentle, Dallas has ranked in the US Top 500 since records began in 1880. Never super popular but surprisingly never out of style, Dallas is given to nearly 1400 boys in the US every year.

Though Dara in the U.S. would be considered mainly a girls' name – the most recent count is 10 times as many girls given the name last year than boys – it's a boys' name in Ireland, where it's in the Top 100 along with variations Daire and Darragh.

Devilishly handsome, Devin arrived as Kevin was moving out. Not to be confused (though it often is) with the English place-name Devon. While both Devin and Devon are flagging somewhat for boys, the names have dropped out of the Top 1000 for girls, making it more a masculine and less a unisex name these days.

A name with a bit of glamor but also cowgirl vibes, Dallas entered the US Top 1000 for girls in 1992. It fell out of style during noughties, but reappeared in 2012 when other gender neutral names like River, Sawyer, Rowan, and Blake were also climbing fast.

Also Anglicized as Dara and also spelled Daire in its native form, Darragh has an undeniably rugged appeal. It's used for both girls and boys in Ireland, but it's very popular in particular for boys.

Devlin is an Irish name that's fresher and even more devilish than Devin.

The earliest written record of this surname occurs in the thirteenth century, when an O'Devlin was appointed Bishop of Kells in 1211.

Dermot is an appealing, relatively undiscovered Irish mythological hero's name long popular in the Old Country, and imported into the American consciousness by actor Dermot Mulroney. We see it in the next Celtic wave following Connor and Liam.

Sadly, this strong Celtic name often has "of the sorrows" attached to it because of the tragic character in Irish legend. Also a bit drab when compared with newer Irish imports.

Spirited and bubbly, but handsome and preppy too, Darby is a surname style choice that fits in well with the likes of Alby and Lennox.

Donal is, yes, just Donald with the final d cut off, but that somehow gives it a jauntier, fresher feel. Donal Logue is a Canadian actor and Donal Skehan is an Irish cookbook author.

Different origin from the Welsh Dylan, but increasingly used as a variant spelling to honor Bob Dylan or Dylan Thomas. Still, the Dylan spelling is found 20 times as often as Dillon.

With both the Dillon and Dylan spellings, usage of this gender-neutral names runs about ten to one boys to girls. But Dylan is used about 20 times as often as Dillon for both genders. Which might be a vote in favor of Dillon, though for better or worse, this spellings distances the name from singer Bob and poet Thomas.

An Irish surname possibility for those who like Daley, Royal, Dougal, and Dolan, though it may sound too much like doily to catch on for modern boys. Nevertheless, it was fairly well used in the 20th century, popular in the 30s, 40s, and 50s when it reached the Top 200 at one point.