Wonderfully Unique.

Arwen is well known as princess of the Elves in Tolkien's Lord of the Rings. The author took inspiration from Welsh for many of his character names, and indeed Arwen and its masculine counterpart Arwyn do have a modest history of use as legitimate Welsh names, deriving from the -wyn suffix ("fair, blessed") plus an intensifying prefix.

For a name that was in the Top 20 for a whole decade – the 1930's – Marilyn has attained the status of almost a one-person name. Just say the name Marilyn, and most people will know who you mean. Yet strangely enough, though Marilyn Monroe (born Norma Jean and renamed in tribute to earlier star Marilyn Miller) was the sex symbol of her generation, very little stardust adhered to her name. In fact, when Mariah Carey wished to honor the star in her daughter's name, she chose to call her Monroe rather than Marilyn.

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.

Yes, Spencer makes a plausible and powerful female choice these days, though still thought of as primarily for boys. Kelsey Grammer used it for his daughter in the 1980's. Spencer made its first appearance on the girls' Top 1000 in 2017.