Actually, "persons" is the plural of "person". If you're going to attach your own meanings to words, it rapidly becomes impossible to have any meaningful communication. This is a thread about theology, so the proper definition of "person" is the one theologians use. When people say "the Holy Spirit is a person," they are using the word the way I am using the word. They do not mean "the Holy Spirit is a human being".
"Being" is problematical anyway. A rock is a "being" (it exists), but it is not a "person" (according to the way theologians and philosophers use the word) because it has no rational nature.