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verb af·firm \ə-ˈfərm\

Simple Definition of affirm

  • : to say that something is true in a confident way

  • : to show a strong belief in or dedication to (something, such as an important idea)

  • law : to decide that the judgment of another court is correct

Source: Merriam-Webster's Learner's Dictionary

Full Definition of affirm

  1. transitive verb
  2. 1 a :  validate, confirm b :  to state positively <he affirmed his innocence>

  3. 2 :  to assert (as a judgment or decree) as valid or confirmed

  4. 3 :  to express dedication to <affirm life>

  5. intransitive verb
  6. 1 :  to testify or declare by affirmation as distinguished from swearing an oath

  7. 2 :  to uphold a judgment or decree of a lower court

affirmableplay \ə-ˈfər-mə-bəl\ adjective
affirmanceplay \ə-ˈfər-mən(t)s\ noun

Examples of affirm in a sentence

  1. We cannot affirm that this painting is genuine.

  2. They neither affirmed nor denied their guilt.

  3. laws affirming the racial equality of all peoples

  4. They continued to affirm their religious beliefs.

  5. The decision was affirmed by a higher court.

Origin of affirm

Middle English affermen, from Anglo-French afermer, from Latin affirmare, from ad- + firmare to make firm, from firmus firm — more at firm

First Known Use: 14th century

Synonym Discussion of affirm

assert, declare, affirm, protest, avow mean to state positively usually in anticipation of denial or objection. assert implies stating confidently without need for proof or regard for evidence <asserted that modern music is just noise>. declare stresses open or public statement <declared her support for the candidate>. affirm implies conviction based on evidence, experience, or faith <affirmed the existence of an afterlife>. protest emphasizes affirming in the face of denial or doubt <protested that he really had been misquoted>. avow stresses frank declaration and acknowledgment of personal responsibility for what is declared <avowed that all investors would be repaid in full>.

AFFIRM Defined for Kids


verb af·firm \ə-ˈfərm\

Definition of affirm for Students


  1. :  to declare that something is true <The man affirms that he is innocent.>

Law Dictionary


transitive verb af·firm \ə-ˈfərm\

Legal Definition of affirm

  1. 1 :  to assert as true or factual

  2. 2 :  to assert (as a judgment) as valid or confirmed <affirmed the lower court's ruling> — compare remand, reverse

  3. intransitive verb
  4. 1 :  to make a solemn declaration under the penalties of perjury in place of swearing an oath to which one conscientiously objects

  5. 2 :  to uphold the judgment or actions of a lower court <the appeals court affirmed>

affirmance \ə-ˈfər-məns\ play noun
affirmation \ˌa-fər-ˈmā-shən\ play noun

Seen and Heard

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tending to dismiss important matters

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