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

In his first full season in the majors, Hader assured himself a spot in the NL bullpen weeks ago by becoming a strikeout sensation and nearly unhittable for much of the first half. Tom Haudricourt, Milwaukee Journal Sentinel, "Lorenzo Cain, Christian Yelich and Josh Hader are in the All-Star Game and Jesus Aguilar could join them," 8 July 2018 Membership in one of these groups assured one of a proper burial, much like burial insurance does today. Andrew Boyd,, "St. Louis Cemetery No. 1: Is Marie Laveau where they say she is?," 22 May 2018 Their first-ever Mountain West title assured the Broncos an automatic NCAA Tournament berth, which is also a first. Rachel Roberts, idahostatesman, "Boise State draws familiar Pac-12 power for NCAA Tournament opener | Idaho Statesman," 13 May 2018 In the email announcement, von Gootkin and Kowalczyk assured customers that a Whiskey Pass, gift certificate or Groupon would be accepted at the new location this fall. Leeanne Griffin,, "Onyx Spirits Plans Move; Will Close East Hartford Tasting Room," 9 May 2018 That means if there is money in the estate to pay unsecured claims — debts that are not assured payment — at the end of the bankruptcy, students would receive a share. Danielle Douglas-gabriel,, "Defunct for-profit college firm ITT's former executives settle fraud charges," 10 July 2018 Mexico finished second in Group F and now has the daunting task of playing Brazil, which won Group E. Brazil’s victory assured that Neymar joined Lionel Messi and Cristiano Ronaldo in the knockout round. Ann Killion,, "At World Cup, surprises are the new norm," 27 June 2018 Users and app developers will have to redirect their software to Rebble’s servers, and Berry assures users that things won’t look too different once the servers are switched. Shoshana Wodinsky, The Verge, "Pebble smartwatches could be kept alive by an unofficial developer group called Rebble," 15 June 2018 State officials assured the affected voters that their ballots would be counted, but only about 10 percent ended up voting, according to elections officials. Michael Dresser,, "Thousands of Maryland voters may have skipped primary because of MVA election error," 13 July 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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Phrases Related to assure

assure oneself

Statistics for assure

Last Updated

12 Sep 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).


a magnificent or impressive array

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