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verb as·sume \ə-ˈsüm\

Simple Definition of assume

  • : to think that something is true or probably true without knowing that it is true

  • : to begin (a role, duty, etc.) as a job or responsibility

  • : to take or begin to have (power, control, etc.) in a job or situation

Full Definition of assume


  1. transitive verb
  2. 1 a :  to take up or in :  receive b :  to take into partnership, employment, or use

  3. 2 a :  to take to or upon oneself :  undertake <assume responsibility> b :  put on, don c :  to place oneself in <assume a position>

  4. 3 :  seize, usurp <assume control>

  5. 4 :  to pretend to have or be :  feign <assumed an air of confidence in spite of her dismay>

  6. 5 :  to take as granted or true :  suppose <I assume he'll be there>

  7. 6 :  to take over (the debts of another) as one's own

as·sum·abil·i·typlay \-ˌsü-mə-ˈbi-lə-tē\ noun
as·sum·able play \-ˈsü-mə-bəl\ adjective
as·sum·ably play \-blē\ adverb

Examples of assume

  1. I assumed he was coming, so I was surprised when he didn't show up.

  2. She assumed from his expression that he was confused.

  3. We'll be arriving around noon. That's assuming that our flight is on time.

  4. The king assumed the throne when he was very young.

  5. Under certain conditions, the chemical will assume the appearance of ice.

Origin of assume

Middle English, from Latin assumere, from ad- + sumere to take — more at consume

First Known Use: 15th century

Synonym Discussion of assume

assume, affect, pretend, simulate, feign, counterfeit, sham mean to put on a false or deceptive appearance. assume often implies a justifiable motive rather than an intent to deceive <assumed an air of cheerfulness around the patients>. affect implies making a false show of possessing, using, or feeling <affected an interest in art>. pretend implies an overt and sustained false appearance <pretended that nothing had happened>. simulate suggests a close imitation of the appearance of something <cosmetics that simulate a suntan>. feign implies more artful invention than pretend, less specific mimicry than simulate <feigned sickness>. counterfeit implies achieving the highest degree of verisimilitude of any of these words <an actor counterfeiting drunkenness>. sham implies an obvious falseness that fools only the gullible <shammed a most unconvincing limp>.

ASSUME Defined for Kids


verb as·sume \ə-ˈsüm\

Definition of assume


  1. 1 :  to begin to take on or perform <assume responsibility> <assumed the presidency>

  2. 2 :  to take or begin to have <The problem assumes greater importance now.>

  3. 3 :  to pretend to have or be <We both assumed an air of weary worldliness … — Richard Peck, A Long Way From Chicago>

  4. 4 :  to accept as true <I assume you're right.>

Seen and Heard

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February 11, 2016

the holder of an office

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