adj. & adv.
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).
1. in an a priori manner.
2 as far as one knows; presumptively.
Etymology: L, from what is before