presumption is on the Academic Word List.

Singular
presumption

Plural
presumptions

  1. (countable) A presumption is a belief that something is true without knowing for sure.
    The presumption that he is the father of his wife's children turned out to be wrong.
    The strong presumption of guilt has changed to a stronger presumption of innocence.
  2. (uncountable) Presumption is behaviour that is too friendly or too confident.

Synonyms

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