en·​sure in-ˈshu̇r How to pronounce ensure (audio)
ensured; ensuring

transitive verb

: to make sure, certain, or safe : guarantee

Did you know?

Do you ensure or insure?

There is considerable confusion about whether ensure and insure are distinct words, variants of the same word, or some combination of the two. They are in fact different words, but with sufficient overlap in meaning and form as to create uncertainty as to which should be used when. We define ensure as “to make sure, certain, or safe” and one sense of insure, “to make certain especially by taking necessary measures and precautions,” is quite similar. But insure has the additional meaning “to provide or obtain insurance on or for,” which is not shared by ensure. Some usage guides recommend using insure in financial contexts (as in “she insured her book collection for a million dollars”) and ensure in the general sense “to make certain” (as in “she ensured that the book collection was packed well”).

Choose the Right Synonym for ensure

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

Example Sentences

A combination of … personal courage, dashing leadership from the front, willingness to share the toughest rigours suffered by the ordinary soldiers, and a liberal dose of sheer good fortune ensured his stature as a great general. Paul Cartledge, History Today, July 2004 Indeed, even though she's been off the mainstream radar for more than a decade, her passionate love for and commitment to rock & roll have ensured that she's managed to make a steady living. Tom Sinclair, Entertainment Weekly, 24 Nov. 2000 At 20, [Kobe] Bryant is already living the modern American dream, a $70 million man on the NBA's glamour team in the nation's starriest city. His acrobatic moves make him the envy of teenage boys and his good looks and megawatt smile a heartthrob for teenage girls, ensuring his status as one of the NBA's premier pitchmen … Allison Samuels et al., Newsweek, 31 May 1999 They took steps to ensure the safety of the passengers. regulations that ensure the wholesomeness of our food
Recent Examples on the Web Donor sperm has to be frozen and quarantined for three to six months to ensure that the donor does not have infectious diseases that could be transmitted through insemination, Dr. Thornton said. Alexis Benveniste, ELLE, 23 Nov. 2022 South Florida nonprofits, organizations and volunteers are leading donation efforts to ensure everyone has a happy holiday season. Kari Barnett, Sun Sentinel, 22 Nov. 2022 Doing so would ensure that more people are housed and that the human and fiscal costs of homelessness are reduced, Carr said. Andrew Khouri, Los Angeles Times, 19 Nov. 2022 The memo said each club should ensure that its travel arrangements do not include providing alcohol service at any time and that teams should also take appropriate steps to confirm that alcohol is not available at its facility. Chris Bumbaca, USA TODAY, 19 Nov. 2022 The uncrewed Artemis 1 flight is meant to be a test run to ensure NASA’s equipment is safe for future human occupants. Carlyn Kranking, Smithsonian Magazine, 16 Nov. 2022 The Queen Mary 2, the largest passenger ship at the time it was built, is downright balletic compared to the Felicity Ace, which is about half the size; the cruise ship has to be more agile to ensure that passengers don’t get tossed around. Andrew Lawrence, Popular Mechanics, 14 Nov. 2022 Moreover, partnering with third-party logistics providers to stabilize the transportation capacity is crucial to ensure the supply cycle remains undisturbed and doesn’t attract additional overbearing costs. Pushkar Mukewar, Forbes, 11 Nov. 2022 For years, a system was in place to ensure the far right didn’t achieve this. Constant Méheut, New York Times, 10 Nov. 2022 See More

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

Word History


Middle English, from Anglo-French ensurer, alteration of assurer — more at assure

First Known Use

1660, in the meaning defined above

Time Traveler
The first known use of ensure was in 1660

Dictionary Entries Near ensure

Cite this Entry

“Ensure.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ensure. Accessed 29 Nov. 2022.

Kids Definition



en·​sure in-ˈshu̇(ə)r How to pronounce ensure (audio)
ensured; ensuring
: to make sure, certain, or safe : guarantee

More from Merriam-Webster on ensure

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