Usage of Assure, Ensure, and Insure
In the centuries that ensure, assure, and insure have been in use, each member of the trio has at times been defined as a synonym of the others. Today, however, distinctions are generally made. Assure is most often used when someone is removing, or attempting to remove, doubt.
Ensure typically applies when something is made sure, certain, or safe.
Insure sometimes has this same meaning, but more often it is used when insurance is involved,
or, with the word against, when there is an effort to prevent something.
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”).
Examples of insure in a Sentence
William Safire, New York Times Magazine, 24 Aug. 1986
… his sudden fame probably insured a backlash.
—Calvin Tomkins, New Yorker, 6 Dec. 1982
The fact that by supplying his uncle with an amusing mistress he would insure against any awkward second marriage was merely a fortunate coincidence.
—Mollie Hardwick, Emma, Lady Hamilton, 1969
We insured our house against fire and flood damage.
I found a company that will insure my car for less than I've been paying.
This policy will insure your car against theft.
She had difficulty finding a company that would insure her.
They take great care to insure the safety and security of their home.
We hope that careful planning will insure success.
Nicholas Florko, The Atlantic, 7 Nov. 2025
The Court’s nondelegation doctrine is meant to insure that Congress does not hand over its power to make law.
—Jeannie Suk Gersen, New Yorker, 6 Nov. 2025
But this worsening food crisis now on a collision course with the issue Democrats are holding firm to fix in this shutdown, looming, skyrocketing health care costs for some 20 million Americans insured through the Affordable Care Act.
—ABC News, 2 Nov. 2025
The jewels stolen from the Louvre, however, were not privately insured.
—Dave Smith, Fortune, 30 Oct. 2025
See All Example Sentences for insure
Cite this Entry
“Insure.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/insure. Accessed 8 Nov. 2025.
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