adj. & adv.
--adj.
1. (of reasoning) deductive; proceeding from causes to effects (opp. A POSTERIORI).
2 (of concepts, knowledge, etc.) logically independent of experience; not derived from experience (opp. EMPIRICAL).
3 not submitted to critical investigation (an a priori conjecture).
--adv.
1. in an a priori manner.
2 as far as one knows; presumptively.
Derivatives:
apriorism n.
Etymology: L, from what is before