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



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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 But a win over the Bengals (2-10-1) — or a loss by Cleveland on Sunday — would assure the Steelers of an AFC North title and at least one home playoff game at Heinz Field. Mark Heim |, al, "Steelers vs. Bengals live stream (12/21): How to watch NFL Week 15 online, TV, time," 21 Dec. 2020 During the recruiting process, all coaches assure parents their daughters will be taken care of on campus, but Close’s message felt unique, Miller said. Los Angeles Times, "UCLA’s Cori Close helping her players, and herself, grow in trying times," 21 Dec. 2020 In the Netflix series, which follows the Windsor family throughout the reign of Queen Elizabeth II, Diana’s friends assure her after the interview that Charles’s strange response was probably the result of nerves. Washington Post, "As ‘The Crown’ tackles recent history with Princess Diana, the show hits a nerve," 19 Nov. 2020 Yet that doesn't assure them of anything in a season with so much uncertainty. Steve Megargee, Star Tribune, "Wisconsin moves on without wondering what could have been," 15 Oct. 2020 Media piracy has seen several golden ages before, including Napster’s heyday (1999-2002) and The Pirate Bay’s peak years (2003-2008), but Warner and Disney’s new strategies all but assure 2021 will be the dawning of a platinum age. Abigail De Kosnik, Wired, "2021 Will Launch the Platinum Age of Piracy," 12 Dec. 2020 Dombrowski, the only GM or team president to lead three different franchises to a World Series, likely will be in the Hall of Fame one day without this final challenge, but this could assure his induction. Bob Nightengale, USA TODAY, "'Retool, not a rebuild': Phillies bet big on Dave Dombrowski leading team back to glory," 11 Dec. 2020 Take steps to save the planet and assure everyone’s future. Tribune Content Agency, oregonlive, "Horoscope for Dec. 2, 2020: Taurus, be energized, hip; Sagittarius, take steps to save the planet," 2 Dec. 2020 In February, the Corps proposed a $3.2 billion, 50-year program of levee improvements for both levee systems that would assure they are returned to the 100-year surge risk reduction level by 2023 and remain at that level through 2073. Mark Schleifstein,, "Tulane study: Corps can elevate New Orleans levees to 200-year levels without OK from Congress," 24 Nov. 2020

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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Time Traveler for assure

Time Traveler

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

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Statistics for assure

Last Updated

28 Dec 2020

Cite this Entry

“Assure.” Dictionary, Merriam-Webster, Accessed 26 Jan. 2021.

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More Definitions for assure


How to pronounce assure (audio)

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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