noun as·sump·tion \ə-ˈsəm(p)-shən\

Definition of assumption

  1. 1 :  a taking to or upon oneself <the assumption of a new position>

  2. 2 :  the act of laying claim to or taking possession of something <the assumption of power>

  3. 3a :  an assuming that something is true <a mistaken assumption>b :  a fact or statement (such as a proposition, axiom (see axiom 2), postulate, or notion) taken for granted

  4. 4a :  the taking up of a person into heavenb capitalized :  August 15 observed in commemoration of the Assumption of the Virgin Mary

  5. 5 :  the taking over of another's debts

  6. 6 :  arrogance, pretension

Examples of assumption in a sentence

  1. I made the assumption that he was coming, so I was surprised when he didn't show up.

  2. He will come home tomorrow. At least, that's my assumption.

  3. Many scientific assumptions about Mars were wrong.

  4. I'm telling you our arrival time on the assumption that you will check to see whether or not our flight is on time before you come to the airport.

  5. Her plan is based on the underlying assumption that the economy will improve in the near future.

  6. her assumption of the presidency

  7. the buyer's assumption of debt

Origin and Etymology of assumption

Middle English, from Late Latin assumption-, assumptio taking up, from Latin assumere —see assume

First Known Use: 13th century

ASSUMPTION Defined for Kids


noun as·sump·tion \ə-ˈsəmp-shən\

Definition of assumption for Students

  1. 1 :  the act of taking on <the assumption of power>

  2. 2 :  something accepted as true <I'm making plans on the assumption that you will be here.>

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