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assumption JUST WRITTEN FOR YOU

/əˈsʌmp.ʃən/ · as.sum.p·tion
noun
  1. The act of assuming, or taking to or upon oneself; the act of taking up or adopting. His assumption of secretarial duties was timely.
  2. The act of taking for granted, or supposing a thing without proof; a supposition; an unwarrantable claim. Their assumption of his guilt disqualified them from jury duty.
  3. The thing supposed; a postulate, or proposition assumed; a supposition. The assumption of a spherical Earth was a crucial step in the development of modern astronomy.
Did you know? The concept of assumption has been a crucial aspect of scientific inquiry, as scientists often make assumptions about the natural world in order to develop and test theories.
Written by Lexi Wordsworth, Dictionary Editor 0 lookups Added Jul 15, 2026