Pre-sŭp'po-sĭ'tion, n.

(-zĭsh'un), n. [Eng. prefix pre and supposition; Fr. présupposition, Sp. presuposición, It. presupposizione.]

1. The act of presupposing; supposition or antecedent implication; presumption.
2. That which is presupposed; previous supposition or surmise.