Antediluvian definition

Antediluvian

Topics Antediluvian Definition

WordNet

(1) So extremely old as seeming to belong to an earlier period

"A ramshackle antediluvian tenement"

"Antediluvian ideas"

"Archaic laws"

(2) Of or relating to the period before the biblical flood

"Antediluvian man"

(3) A very old person

(4) Any of the early patriarchs who lived prior to the Noachian deluge

WiktionaryText

antediluvian

Extremely ancient or antiquated; old; prehistoric.
Supremely dated.

Those ideas are antediluvian.
Pertaining or belonging to the time period prior to a great or destructive flood or deluge
Pertaining or belonging to the time prior to Noah's Flood.