It has been commented that you don't know anyone with the name of Adonai. Well I guess I'm the first one then because my middle name is Adonay, but my parents intentionally misspelled it substituting the 'i' for a 'y'.
Just as with any other name, anyone that wants to can name their son Adonai. If it is against someone's beliefs, they can chose not to do it, but they shouldn't make of their beliefs a general rule for the whole humanity. There are people that consider Christianity or Islam just another mythology, so it's fine if they want to name their son Allah or Yahve or Jehovah or Adonai as it is fine for them to name their son Zeus or Apollo or Hermes or Ouranos or Mars or Venus or Jupiter.
Beautiful name. I agree with the previous poster completely. Please don't soil other's impression of this name through your own beliefs; they are not universal. That being said, I would love to name my daughter this. It sounds like such a feminine name, even if it's listed as masculine. The meaning doesn't concern me much; at least it isn't "asshole"!
Though it is a free country and you *can* name someone whatever you want to, this is not a name. It is the same thing as naming a kid "My Lord" which is pretty weird.