Merry 2

Doesn't sound boy-ish at all to me.

How is it masculine?

Considering Peter Jackson made Merry and Pippin gay, this would be a quite unfortunate name for a little boy to have.

There was a boy in my older brother's class called Merry. I like it as a nickname for Montgomery :)

I have a friend who I now call Merry. However, I discourage parents from thinking this means they ought to name a boy Merry. It just wouldn't work (it's different for my friend because it's a nickname). However, if you're a Tolkien fan, I think it would be interesting and somewhat cool to give this name to a girl.