also: かげん
Used when someone says something that goes beyond the truth, often in negative constructions like 過言ではない (it is no exaggeration to say).
It is no exaggeration to say that he is a genius.
I think that's a bit of an overstatement.
misstatement; gaffe; slip of the tongue
Refers to an unintentional mistake in speech, such as saying something incorrect or inappropriate. Less common than the exaggeration sense.
His misstatement at the meeting became a problem.
失言 is the everyday word for a verbal slip or gaffe, often with social or political fallout, whereas 過言 in its misstatement sense is rarer and more literary.
過言 is a stiff, literary word almost always used in the set phrase 〜と言っても過言ではない, whereas 言い過ぎ is the everyday word for having said too much.
Standard kanji form; the reading かごん is the most common.
Rare alternate reading; かごん is overwhelmingly preferred in modern Japanese.
Compound of 過 (excess, over-) and 言 (word, speech). The literal meaning is 'excessive words'.