Antediluvian is used for something that belongs to a very ancientbelonging to a very remote past, long ago in history time, especially in a biblicalconnected with the Bible or stories from it or figurativeusing words in a nonliteral, symbolic way sense. It can also refer to a person from before the biblical flood.

Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Pronunciation

AI-generated pronunciation audio (OpenAI).

Accent: General American English

IPA: /an-tee-di-LOO-vee-uhn/

Easy pronunciation: an-tee-di-LOO-vee-uhn (approximate spelling).

Stress: Primary stress on LOO.

Adjective meaning very old-fashioned or belonging to an earlier era.

Reviewed with OpenAI Decisions. Assessment: uncertain — manual review needed. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Antediluvian Meaning

very old-fashioned or from a much earlier time

Part of speech: adjective

Definition: so extremely old as seeming to belong to an earlier period

Example: The museum displayed an antediluvian machine that still somehow worked.

Synonyms for this meaning:

• antiquated — A strong everyday substitute when something is old-fashioned or out of date.
• archaic — Works well when something feels very old or belongs to an earlier era.

Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Other Meanings of Antediluvian

Meaning 2

from the time before the biblical flood

Part of speech: adjective

Definition: of or relating to the period before the biblical flood

Example: The story described an antediluvian world.

Synonyms for this meaning:

• antediluvial — A direct synonym in this specific biblical-historical sense.

Meaning 3

an extremely old person

Part of speech: noun

Definition: a very old person

Example: He joked that he felt like an antediluvian after the long hike.

Synonyms for this meaning:

• ancient — Used figuratively for a very old person, though less precise and often informal.

Meaning 4

one of the early biblical patriarchs before the flood

Part of speech: noun

Definition: any of the early patriarchs who lived prior to the Noachian deluge

Example: In the text, Adam and other antediluvians are treated as figures from the earliest age.

Synonyms for this meaning:

• antediluvian patriarch — Matches this religious-historical noun sense directly.

Reviewed with OpenAI Decisions. Assessment: uncertain — manual review needed. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Antediluvian Synonyms

Similar Meaning

• antiquated
• archaic

before the biblical flood

• antediluvial

a very old person

• ancient

an early patriarch before the flood

• antediluvian patriarch

Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Common Mistakes

• Not every use means just 'old.' In biblical writing, antediluvian refers specifically to the time before the flood.
• The noun sense for a very old person is rare and mostly figurative.
• Do not confuse antediluvian with antebellum or antiquated; they are different words with different histories.

Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.

Frequently Asked Questions

What does antediluvian mean?

Most often, antediluvian means very old-fashioned or belonging to an extremely early period. In religious contexts, it can also mean before the biblical flood.

Is antediluvian a positive or negative word?

Usually it is neutral or slightly negative when describing old-fashioned ideas, objects, or systems.

What are the best synonyms for antediluvian?

For the common adjective sense, the best synonyms are antiquated and archaic. Other senses have more specific equivalents, such as antediluvial in the biblical-historical sense.

Reviewed with OpenAI Decisions. Assessment: accurate. Checked: 2026-10-21. AI assessment; not a guarantee of accuracy.