The word "not" is a basic English adverb used to indicate negation, denial, or contradiction. It is used to form negative sentences or phrases, essentially indicating that something is false or untrue. For example, if you say "It is not raining," you are expressing that rain is not occurring.
The word "not" comes from the Old English "nē," which evolved into "not" as a contraction of the term "naught." Its use has persisted throughout the history of the English language, serving as a fundamental component for forming negatives.
Feel free to ask more about the use of "not" in different contexts!