A priori and a posteriori are terms that are used especially in logic and philosophy. A priori is from Latin ā priōrī, which means literally, "from what is earlier."

“A priori” and “a posteriori” refer primarily to how, or on what basis, a proposition might be known. In general terms, a proposition is knowable a priori if it is knowable independently of …

A PRIORI definition: 1. relating to an argument that suggests the probable effects of a known cause, or using general…. Learn more.

An a priori argument, reason, or probability is based on an assumed principle or fact, rather than on actual observed facts. In the absence of such evidence, there is no a priori hypothesis to …

Definition of priori in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

Define a priori. a priori synonyms, a priori pronunciation, a priori translation, English dictionary definition of a priori. adj. 1. Proceeding from a known or assumed cause to a necessarily …

A priori is a term applied to knowledge considered to be true without being based on previous experience or observation. In this sense, a priori describes knowledge that requires no evidence.

Factsheet What does the adverb a priori mean? There are three meanings listed in OED's entry for the adverb a priori. See ‘Meaning & use’ for definitions, usage, and quotation evidence.

Dec 24, 2025 · Learned borrowing from Medieval Latin ā priōrī (“involving reasoning from cause to effect; from first principles”, literally “from the former”). a priori (comparative more a priori, …

A PRIORI meaning: relating to what can be known through an understanding of how certain things work rather than by observation