Mumbo-jumbo is language that sounds important or technical but does not really help you understand — a contract full of legal mumbo-jumbo, or a gadget manual that is all mumbo-jumbo. People say it when they feel someone is hiding behind fancy words, or when the talk feels empty and showy. It is informal, a little teasing or annoyed, not a word for a formal essay. Though actually it can also mean any confusing ritual or nonsense, not only specialist talk. You do not count it: you do not say “a mumbo-jumbo.”