Antediluvian and Ancients

Antediluvian noun - A person with old-fashioned ideas.

Ancients is a synonym for antediluvian. In some cases you can replace term "Ancients" with "Antediluvian", this nouns are similar.

Ancients noun - People who lived in times long past (especially during the historical period before the fall of the Roman Empire in western Europe).

Antediluvian is a synonym for ancients. You can use "Antediluvian" instead a noun "Ancients".