This Scottish place name and surname was more popular for boys in the US until the mid-1940s; in the UK, the Leslie spelling is predominantly masculine, with Lesley widely used as the feminine variant. Now ranking in the mid-400s for girls and not at all for boys in the US, it could be time to bring this smart, subtle nature name back, especially considering the current popularity of -ley names for both sexes.

Fun fact: Marion was the birth name of movie star John Wayne. Although commonly thought of as a female name today, it was actually more popular for boys until the late 19th century, and was given to roughly equal numbers of boys and girls throughout the 1970s-2000s.

Renowned English author Evelyn Waugh pronounced his name "EEV-lin" (fun fact: his first wife, also named Evelyn, was referred to as "She-velyn"). But "EV-uh-lin" also works, and is probably the most familiar pronunciation of the name today.

It may have peaked at #1 for girls in 1991 and 1992 in the US, but Ashley actually has a long history as a male given name, as evidenced by the sensitive Ashley Wilkes in Gone With the Wind. It's always been more popular for boys in England and Wales, where it currently ranks at #414.

While the variation Carmine is more familiar for boys, Carmen has also been used as a masculine name; consider the very macho Carmen Basilio — the American boxer famous for defeating the great Sugar Ray Robinson — or composer Carmen Dragon.

Spanish and Italian forms Carmelo and Carmello are also quite popular in the US, with Carmelo ranking in the Top 1000.

Extremely amiable, open-sounding surname that's gradually being taken over by the girls.

This name leapt into the female column via vixen Alexis Carrington on 'Dynasty" in the 1980s. It's more popular for girls, but it's still a widely used boys' names and is one of the most popular unisex names in the US today.

A predominantly male name in the US until the late 1950s, the name continued to rise for both sexes for both sexes for a further decade, before starting to decline for boys. Despite dropping out of the boys' Top 1000 in 2002, Kelly retains a rugged Irish charm.

The first famous Paris was a mythological prince of incredible beauty. The most recent was media darling Paris Hilton, inspirer of a generation of baby-girl namesakes. But since Pierce Brosnan and other celebs have continued to use it for their sons, the name retains some masculine identity. For girls, it jumped from #464 to #412 in the past year alone.

Deriving from the Roman cognomen Vivianus, Vivian was originally a masculine name, with Vivien being a feminine soundalike coined by Alfred Lord Tennyson for the Lady of the Lake in his famous poetic adaptation of the legend of King Arthur. It has since become a much more popular choice for girls in the US, but retains a refined British charm which sees it cropping up occasionally for boys in the Telegraph birth announcements.

This courtly old Southern name has several cool male bearers: NFL player Courtney Brown, British jazz musician Courtney Pine, and Barbados-born economist Courtney Blackman, to name but a few.

This lively Scottish surname is an anglicized form of the Gaelic Mac Coinnich, Coinnich being one of the original Gaelic forms of Kenneth.

The name of the longest river in the British Isles rose to the US Top 25 for girls in the 1970s and the Top 100 for boys, but has fallen off the Top 1000 for both genders. At the latest count, the name Shannon was given to about 200 babies in the US, about a third of those boys. As a favorite Irish name, Shannon has now been supplanted by newcomers such as Saoirse and Seanan.

It may be the hippest of hispter neighborhoods, but as a baby name Brooklyn is now on the decline: down from a peak of 120 births for boys in 1999, and over 7000 births for girls in 2011.

Despite its distinguished pedigree and popularity in Israel, Disney's Little Mermaid cartoonized Ariel in the US, at least in some people's minds. But it was used for a male character in Shakespeare's The Tempest centuries ago.

Southern name still occasionally heard in a male context (author Shelby Foote and the son of singer/sitcom star Reba McEntire), but it's much more associated with girls.

Lindsay is one of the few truly unisex names (rather than being a name that has changed genders). Over time the ey ending was usually reserved for women and the ay ending reserved for men, although both spellings are overwhelmingly female these days.

Baby girl Danas outnumber baby boys with the name nearly ten to one. But Dana is an attractive, sleek name that can certain work for babies of either gender.

Lindsey as a masculine name has Anglo-Saxon origins, originally derived from the Old English place name 'Lindesege,' meaning 'island of linden trees' or 'Lincoln's marsh.' While now more commonly recognized as a feminine name in the United States, Lindsey has historically been used for boys in the United Kingdom and Scotland. The name peaked in popularity for boys in the 1970s and 1980s before shifting predominantly to female usage. Notable male Lindseys include American politician Lindsey Graham. The name carries associations with nature and English heritage, and offers a soft yet distinguished sound for male bearers. Many parents now choose it primarily for girls, making it a less common but distinctive choice for boys.

Deriving from an English locational surname meaning "white island", Whitney was in rare but regular use for boys in the US until the early 1960s, when actress Whitney Blake popularized it for girls. It received a further big boost on the girls' side in the 1980s, thanks to singer Whitney Houston. Now falling rapidly down the rankings, it could be time to reclaim this one for the boys, if only as a neat way to cool-guy nickname Whit.