No, Reason's actual name is Reason. The Reason ML name is similar to Go's "golang" name -- to work around the SEO nightmare the choice of the name really is. Your comment is otherwise correct in that Reason is an alternative syntax for good 'ole OCaml.
IIRC it was simply called Reason at first but then the slightly more descriptive ML was added for better searchability. People call it both Reason and Reason ML now. That seems fine to me :)
You are right it mostly is just a different syntax for OCaml but like in the Erlang/Elixir case there is a bit more to the story (js interop, js ecosystem, new ideas here and there, more diverse community as a result, etc).
I still call it reason, especially when I talk about it with other js developers ;)
