antediluvian (adj.)

"before Noah's flood," 1640s, from Latin ante "before" (from PIE root *ant- "front, forehead," with derivatives meaning "in front of, before") + diluvium "a flood" (see deluge (n.)). Hence (humorously or disparagingly) "very antiquated" (1726). Coined by English physician Sir Thomas Browne (1605-1682). As a noun meaning "person who lived before the Flood," from 1680s. Related: antediluvial (1823).

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Definitions of antediluvian from WordNet
antediluvian (n.)
any of the early patriarchs who lived prior to the Noachian deluge;
Synonyms: antediluvian patriarch
antediluvian (n.)
a very old person;
Synonyms: ancient
antediluvian (adj.)
of or relating to the period before the biblical flood;
antediluvian man
Synonyms: antediluvial
antediluvian (adj.)
so extremely old as seeming to belong to an earlier period;
antediluvian ideas
a ramshackle antediluvian tenement
Synonyms: antiquated / archaic