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Biblical name Cain was, until recently, seldom heard outside of the Old Testament and soap operas. Although Cain's murderous actions will always make this name difficult for some, Cain, Eve and Adam's firstborn, was a farmer - making this a good choice for those with farming connections. Long outshone by Abel, Cain is starting to find a broader audience, helped along by homophones Kane or Caine.

Popular name in Ireland -- it's pronounced ee-mer -- from the legendary wife of Cuchulainn who was supposed to possess the six gifts of womanhood: beauty, voice, speech, wisdom, chastity, and of course, needlework. Is found in the poetry of Yeats.

This Celtic goddess and Arthurian name may sound terminally old-ladyish to many ears--but so did names like Ella and Etta not so long ago. So Enid is yet another forgotten four-letter E-possibility: she's has been M.I.A since 1954.

First-wave Irish name and place name—the poetic name for Ireland—now supplanted by newer alternatives such as Maeve and Delaney.

Eris was the goddess of strife and discord, turned fairy tale and then popular culture figure Maleficent in Sleeping Beauty. Ironic, as her name sounds so much like that of Eros, the god of love.

Of all the botanicals, Fern has been one of the slowest to move back from the front parlor into the nursery, despite the appealing girl character in the children's classic Charlotte's Web. Fern was most popular from the turn of the last century through the 1940s, reaching a high of #152 in 1916. We can certainly see her rejoining the long list of popular greenery names.

Grey is the more common spelling in Britain and Australia. This color name has a softness and ambiguity which makes it equally lovely for a boy or a girl.

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.

This name of a small island off the coast of Scotland is trending upwards along with other I names.

Iris has so much going for it. It's a fashionable flower name. It's a mythological name, from the Greek goddess of the rainbow. And it's a classic name, always ranking in the girls' Top 1000 but now at its highest point ever.

Jack may have fallen from its Number 1 place in England, but in the US it's as popular as it was at its height in the 1920s and 1930s. A durable, cheery, everyman form of John, Jack ranks as one of the most popular boy names starting with J.

Opal is on the verge of a repolishing, following other jewel names like Ruby and Pearl. A Top 100 name during the first two decades of the twentieth century, the opalescent Opal has a good chance of coming back as another O-initial option.

There's Rhys and there's Reese (now more popular for girls) and there's Reece, and we particularly like the traditional Welsh spelling, which entered the list in 2004, possibly influenced by Jonathan Rhys Meyers, of The Tudors, and Welsh-born actor Rhys Ifans.

Ruby, vibrant red, sassy and sultry, outshines other revived vintage gem names, with its sparkling resume of cultural references. Ruby is proof of the 100 Year Rule, trending again for the first time since its last heyday in the 1920s.

Ruth, with its air of calm and compassion, was the third most popular name in the 1890s, remaining in the Top 10 through the 1920s. It's still in use today as some parents tiring of Rachel and Rebecca are giving Ruth a second thought. Some see such Old Testament girls’ names as Ruth and Esther rising on the heels of boy equivalents Abel and Moses.

Ryan’s use as a given name was inspired by the surname Ryan, a variation of the Irish O’Riain meaning "son of Rían." Rían is composed of the Irish-Gaelic elements rí, meaning "king" and an, a diminutive suffix. Ryan is considered a unisex name in the US, where variant spellings Ryann and Ryanne are also valid for girls.

Referring to the Scottish Isle of Skye, brings Sky down to earth. This spelling is used more often for girls.