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verb as·sure \ə-ˈshu̇r\

Simple Definition of assure

  • : to make (something) certain

  • : to tell someone in a very strong and definite way that something will happen or that something is true

Full Definition of assure


  1. transitive verb
  2. 1 :  to make safe (as from risks or against overthrow) :  insure

  3. 2 :  to give confidence to <and hereby we know that we are of the truth, and shall assure our hearts — 1 John 3:19(Authorized Version)>

  4. 3 :  to make sure or certain :  convince <glancing back to assure himself no one was following>

  5. 4 :  to inform positively <I assure you that we can do it>

  6. 5 :  to make certain the coming or attainment of :  guarantee <worked hard to assure accuracy>

Examples of assure

  1. I can assure you that you won't be disappointed.

  2. <a minister choosing just the right words to assure the grieving parents of the fallen soldier>

Origin of assure

Middle English, from Anglo-French asseurer, assurer, from Medieval Latin assecurare, from Latin ad- + securus secure

First Known Use: 14th century

Synonym Discussion of assure

ensure, insure, assure, secure mean to make a thing or person sure. ensure, insure, and assure are interchangeable in many contexts where they indicate the making certain or inevitable of an outcome, but ensure may imply a virtual guarantee <the government has ensured the safety of the refugees>, while insure sometimes stresses the taking of necessary measures beforehand <careful planning should insure the success of the party>, and assure distinctively implies the removal of doubt and suspense from a person's mind <I assure you that no harm will be done>. secure implies action taken to guard against attack or loss <sent reinforcements to secure their position>.

ASSURE Defined for Kids


verb as·sure \ə-ˈshu̇r\

Definition of assure


  1. 1 :  to give certainty, confidence, or comfort to <He assured the children all was well.> <She assured herself that the doors were locked.>

  2. 2 :  to inform positively <I assure you that you won't be disappointed.>

  3. 3 :  to provide a guarantee of <assure their safety> <Hard work assures success.>

Seen and Heard

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February 11, 2016

the holder of an office

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