antediluvian

antediluvian \an-tih-duh-LOO-vee-uhn\, adjective:

1. Of or relating to the period before the Biblical flood.
2. Antiquated; from or belonging to a much earlier time.
3. One who lived before the Biblical flood.
4. A very old (or old-fashioned) person.

The other thing that almost always goes with these myths is the notion of an antediluvian civilisation -- something which existed before the flood and was destroyed by it.
-- Graham Hancock, "Castles in the sea", The Guardian, February 6, 2002

. . .a dinosaur garden that is full of such antediluvian plants as mosses and ferns.
-- Barbara Hall, "Cultivating Minds", Washington Post, July 25, 1999

Customs like fox hunting or men's clubs are denounced as barbaric, patriarchal, and antediluvian throwbacks, whereas the truly barbaric, patriarchal, and antediluvian traditions of various stagnant indigenous cultures are viewed with reverence, nostalgia, and envy.
-- Jonah Goldberg, "Who Are We to Judge?", National Review, September 21, 2001

Anyone who asks, "Yes, we can -- but should we?" about any technology risks being branded an antediluvian.
-- Julia Keller, "Killing me Microsoftly with PowerPoint", Chicago Tribune, January 5, 2003

Antediluvian comes from Latin ante-, "before" + diluvium, "flood."