D defs.my
Entry 2 senses Webster, 1913

Presupposition

/prēsˌ-əp-əz-ĭsh'-ən/ · Pre·sup·po·si·tion · IPA /pɹiː.sʌ.pəˈzɪ.ʃ(ə)n/
01 n. The act of presupposing; an antecedent implication; presumption.
  1. 1.
    The act of presupposing; an antecedent implication; presumption.
  2. 2.
    That which is presupposed; a previous supposition or surmise.