presupposition

 
Pronunciation: /ˌpriːsʌpəˈzɪʃ(ə)n/

noun

  • a thing tacitly assumed beforehand at the beginning of a line of argument or course of action: both men shared certain ethical presuppositions about the universe
  • [mass noun] the action or state of presupposing or being presupposed.

Origin:

mid 16th century: from medieval Latin praesuppositio(n-), from the verb praesupponere (see presuppose)