antediluvian
1. [ noun ] (Old Testament) any of the early patriarchs who lived prior to the Deluge
Synonyms: antediluvian_patriarch
Related terms: patriarch
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"

Related terms: old
3. [ adjective ] of or relating to the period before the Biblical flood
Synonyms: antediluvial
Examples:

"Antediluvian man"

Related terms: diluvian diluvian
4. [ noun ] a very old (or old fashioned) person
Related terms: oldster
Similar spelling:   antediluvial