I can understand your frustration! My dh and I had a *terrible* time finding boys names we both liked. We both liked Alexander, which we used for our first son (2nd child). However, finding another was so difficult that we went into the birth of our 3rd child hoping it was a girl, because we had never been able to agree on a boy's name! Of course, he was a boy, and I named him Ethan the day after he was born. It wasn't any of my first choices -- dh had shot all those down. Rather, it was one that we had not seriously considered to that point. DH went along without fuss. I think after seeing me go through the rather difficult birth, he wasn't about to deny me!
  Now it's fine. Ethan is *our* Ethan, and we are happy with his name. (Though I must admit that when my cousin and my younger sister subsequently named their sons names I had really liked and lobbied for, I felt a *teeny* bit jealous!
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Anyhoo, when I was researching names, I remember reading that once a traditionally boys name begins to be used by girls it follows a fairly predictable trajectory: It will be gender neutral for a short time, but within a few decades it will become almost exclusively a girls name. Many boys names have been "lost" this way. I remember that there were some examples on the list that I never imagined had once been male names! Ones that are more recent change-overs include Leslie and Francis. There are some exceptions. Robin comes to mind, probably thanks to Robin Hood and the fact that Robin never became a very commonly used name for girls. One of the names I really loved for our 3rd child was Emerson. DH wasn't crazy about it, but I was still lobbying for it when I heard from 3 different friends that they knew girls named Emerson. (Which I totally don't get -- EmerSON for a girl? As in Ralph Waldo?
 Whatever...)
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Bottom line, I think Ariel is done as a boys name in the United States, at least outside of some ethnic circles. Regardless of whether people have seen the movie or not, there are thousands -- probably many thousands -- of girls under 20 named Ariel. For your son's generation especially, it will be a name associated with female classmates, older sisters, girl cousins, possibly even some of their mothers! I really like the suggestion above of the variation "Aryeh". Maybe that could be a viable alternative. Or just "Ari" as others have suggested. I think Ari is still common enough as a boys name and not used much by girls except as a nickname. (Like Sam, which is still a boy's name, but can be a girl's nickname.)
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Best of luck finding a name you both can live with. It's tough!
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