as·​sure | \ ə-ˈshu̇r How to pronounce assure (audio) \
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

And rest assured, that means most if not all of your favorite characters will be returning, including Maggie Smith, who previously had her doubts about continuing the Crawley family's story. Caroline Hallemann, Town & Country, "The One Character We Definitely Won't See in the New Downton Abbey Movie," 13 Sep. 2019 Rest assured, the Elguera family will have a special celebration when twins Julian and Sophia turn 18 on Nov. 15. Glenn Graham,, "River Hill’s Elguera twins hope to cap varsity soccer careers with titles — and celebrate Argentinian style," 11 Sep. 2019 Other areas don’t honor detainer requests, thinking that avoiding the process completely assures their residents that local officials aren’t communicating at any level with ICE and assisting in deportation efforts. Dan Morse, Washington Post, "Seven undocumented immigrants emerge as sex assault suspects and pull Montgomery County into national debate," 8 Sep. 2019 The outcome seemed assured early as Elsinore, which has made the CIF Southern Section playoffs 17 times during coach Tony Peralta’s 18 seasons at the helm, scored on its first two possessions to create a 14-0 cushion. Barry Faulkner, Daily Pilot, "Fountain Valley football loses at Elsinore in Chris Anderson’s head-coaching debut," 23 Aug. 2019 Coach Kyle Shanahan even suggested recently that the second-year WR wasn’t assured of a starting spot, while rookies Deebo Samuel and Jalen Hurd have created a buzz . Des Bieler, The Denver Post, "Fantasy football 2019: The do-not draft list," 22 Aug. 2019 According to the suit, the victim's parents were assured their son would room only with a same-age camper, as the five-week Opportunities for Personal Success camp was open to boys entering the seventh through 12th grades. Evan Frank, Milwaukee Journal Sentinel, "A Florida family says lax supervision led to assault at St. John's Northwestern Military Academy. Now they're suing.," 16 July 2019 Stinebaugh claimed in the suit, which was later settled, that Landers assured him that the Tourniquet compound paste was free of Viagra before a veterinarian used it on the horses before the races. Kevin Krause, Dallas News, "Pharmacy owner whose drugs led to doped racehorses admits to peddling unsafe equine drugs," 5 July 2019 Jaffa believes that this virtue can best be assured by a cultivation — in the process of jurisprudence — of respect for life, liberty, and the pursuit of happiness. Mike Potemra, National Review, "Born on the Fourth of July," 4 July 2019

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

10 Oct 2019

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 How to pronounce assure (audio) \
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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More from Merriam-Webster on assure

Rhyming Dictionary: Words that rhyme with assure

Thesaurus: All synonyms and antonyms for assure

Spanish Central: Translation of assure

Nglish: Translation of assure for Spanish Speakers

Britannica English: Translation of assure for Arabic Speakers

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).


to wander slowly or to speak indistinctly

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