Simple Definition of antediluvian
: very old or old-fashioned
Full Definition of antediluvian
1 : of or relating to the period before the flood described in the Bible
2 a : made, evolved, or developed a long time ago <an antediluvian automobile> b : extremely primitive or outmoded <an antediluvian prejudice>
Examples of antediluvian
He has antediluvian notions about the role of women in the workplace.
<found evidence in the Middle East of an antediluvian people previously unknown to history>
Origin of antediluvian
ante- + Latin diluvium flood — more at deluge
First Known Use: 1646
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Thesaurus: All synonyms and antonyms for "antediluvian"
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