Nohow means “not in any way” or “not in any situation.” It is almost always humorous, or it copies old dialect speech, especially American or older country British: “I can’t do it, nohow.” You will also see it next to other informal grammar, like ain’t. It is a real word — built like somehow and anyhow — but it is not the English you want in a composition or a careful email. For that, say not at all, in no way, or no way. Using nohow on purpose can make a character in a story sound stubborn, comic, or unschooled. Using it by accident in your own writing can make a teacher think you are being careless.