/an'tee di looh"vee euhn/ , adj.
1. of or belonging to the period before the Flood. Gen. 7, 8.
2. very old, old-fashioned, or out of date; antiquated; primitive: antediluvian ideas.
n.
3. a person who lived before the Flood.
4. a very old or old-fashioned person or thing.
[ 1640-50; ANTE- + L diluvi ( um ) a flood, DELUGE + -AN ]