as·​sure | \ə-ˈshu̇r \
assured; assuring

Definition of assure 

transitive verb

1 : to make sure or certain : convince glancing back to assure himself no one was following

2 : to inform positively I assure you that we can do it.

3 : to make certain the coming or attainment of : guarantee worked hard to assure accuracy

4 : to make safe (as from risks or against overthrow) : insure assured the security of the country

5 : to give confidence to And hereby we know that we are of the truth, and shall assure our hearts … — 1 John 3:19 (King James Version)

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Synonyms & Antonyms for assure


cheer, comfort, console, reassure, solace, soothe


distress, torment, torture, trouble

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Choose the Right Synonym for 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

Examples of assure in a Sentence

I can assure you that you won't be disappointed. a minister choosing just the right words to assure the grieving parents of the fallen soldier

Recent Examples on the Web

Although neither superstars' voices can be heard in the 11-second clip, the brief taste of instrumentals have fans assured that plenty of dancing is about to go down, per the song title's request. Abby Jones, Billboard, "Troye Sivan Shares Preview of Ariana Grande Collaboration 'Dance to This': Listen," 12 June 2018 Rest assured, locals endorse the experience as an authentic, unmissable part of any trip to Dublin. Todd Plummer, Vogue, "A Perfect Weekend Away in Dublin," 11 July 2018 Rest assured, though, Scandrick won’t be quiet for long. Drew Davison, star-telegram, "Josh Doctson impressed with new teammate, former Cowboys DB Orlando Scandrick," 10 July 2018 What's more, coach Brad Stevens has again cobbled together quality lineups and an elite defense despite a host of new faces this season, a skill that should assure a smooth transfer of power as Horford ages. The Si Staff,, "Which Franchise Has the Brighter Future: 76ers or Celtics?," 8 May 2018 Nearly two weeks after Parson issued the vetoes, his director of the Department of Health and Senior Services, Randall Williams, began reaching out personally to stakeholders to assure them the program wasn’t in jeopardy. Jason Hancock, kansascity, "Hospitals fear Parson budget cut could endanger stroke, heart attack, trauma patients," 13 July 2018 Oasis’ technology will be used to assure patients that their data can’t be diverted for other uses. Tom Simonite, WIRED, "How a Startup Is Using the Blockchain to Protect Your Privacy," 11 July 2018 Philadelphia Police Commissioner Richard Ross spoke to local newsrooms Friday to assure them the police department is taking the attack seriously. Aubrey Nagle,, "City turns out for ICE protests, how to steal a house in Philly | Morning Newsletter," 2 July 2018 What adaptations are needed to assure our safety and comfort and relieve our children’s legitimate concerns for our welfare? Jane E. Brody, charlotteobserver, "How to age well and stay in your home," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'assure.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of assure

14th century, in the meaning defined at sense 4

History and Etymology for assure

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

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Statistics for assure

Last Updated

7 Nov 2018

Look-up Popularity

Time Traveler for assure

The first known use of assure was in the 14th century

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More Definitions for assure



English Language Learners 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


as·​sure | \ə-ˈshu̇r \
assured; assuring

Kids Definition of assure

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

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

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

assured; assuring

Legal Definition of assure 

1 chiefly British : insure

2a : to inform positively the seller assured the buyer of his honesty

b : to provide a guarantee of

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Comments on assure

What made you want to look up assure? Please tell us where you read or heard it (including the quote, if possible).


obstinately defiant of authority

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