A priori (Latin, 'from the earlier') is a term used in philosophy and epistemology. A priori or apriori may also refer to: A priori language, a type of constructed language A priori estimate, in the theory of partial differential equations A priori probability, a probability derived by deductive reasoning Apriori algorithm, an algorithm used with databases aPriori Capital Partners, a private equity investment firm Apriori Control (Apriori, LLC), later Reach-In, a technology company See also A posteriori (disambiguation) Priory, a monastery headed by a prior or prioress Ex-ante, a Latin phrase meaning 'before the event'