"antidiluvian" is probably misspelled. Trying antediluvian instead Definition of antediluvian
antediluvian has definitions from the field of Old Testament
1
[ noun ] (Old Testament) any of the early patriarchs who lived prior to the Deluge
2
[ adjective ] so extremely old as seeming to belong to an earlier period

Synonyms

archaic antiquated

Examples

"a ramshackle antediluvian tenement" "antediluvian ideas" "archaic laws"

3
[ adjective ] of or relating to the period before the Biblical flood

Synonyms

antediluvial

Examples

"Antediluvian man"

4
[ noun ] a very old (or old fashioned) person
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