# a priori

> English word · Adjective · IPA /ˌɑː pɹiˈɔːɹi/

## Definitions
1. Self-evident, intuitively obvious.
2. Presumed without analysis.
3. Based on hypothesis and theory rather than experiment or empirical evidence.
4. Developed entirely from scratch, without deriving it from existing languages.

## Etymology
First attested in 1610. Learned borrowing from Medieval Latin ā priōrī (“involving reasoning from cause to effect; from first principles”, literally “from the former”).

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/a-priori