A history, a non-fiction account of the past.
"The new book offers a detailed historic account of the civil rights movement that fills in many missing gaps from official records."
In plain English: A historic event is something that happened long ago and changed history forever.
"The historic discovery changed the course of science forever."
Usage: Use "historic" only when referring to a written record or account of past events, though this specific noun usage is rare in modern English. Most often, people mistakenly use it as a noun where they should simply say "history."
belonging to the past; of what is important or famous in the past
"historic victories"
"historical (or historic) times"
"a historical character"
Very important; noteworthy: having importance or significance in history.
"The signing of the peace treaty was a historic moment that ended decades of conflict across the region."
In plain English: Historic means something important enough in history that it will be remembered for a long time.
"The signing of the treaty was a historic moment for peace."
Usage: Use "historic" to describe an event or moment that is significant because it has had a major impact on history, such as the signing of a peace treaty. Do not use it simply to mean something happened long ago; for events from the past without special importance, use "historical."
The word "historic" comes from the Latin historicus, which was borrowed from the Ancient Greek historikos meaning "exact" or "related to inquiry." It entered English directly from Latin rather than evolving naturally from the combination of "history" and "-ic.