- A period of history generally seen as occurring before the Middle Ages, that is, before the fall of the Roman Empire. Includes Ancient Egypt, Ancient Greece and Ancient Rome.
- (idiomatic) That which happened a long time ago and not worth discussing any more.
- Who cares if he said those things at the beginning of the year? That's ancient history now.
- 1892, Robert Louis Stevenson, The Wrecker:
- I want to have a notion how we stand about the bankruptcy." "O, that's ancient history," cried Jim.
period of history
not worth discussing any more