The term "seishi" (particularly seishi that take the form of danseishi, or dynastic histories, which will be discussed further below) might at first glance be thought to be merely an abbreviation for "true history" as the two characters used are "sei" ("correct, true") and "shi" ("history"), but in fact seishi may include sections where events did not actually occur as described.
正史（特に後述する「断代史」の形式をとる正史）は、その名から「正しい歴史」の略と考えられることがあるが、実際には事実と異なることも記載されている。