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Related to ensure: insure


to secure or guarantee; safeguard; make sure or certain: take measures to ensure success
Not to be confused with:
insure – warrant; protect against loss; to issue an insurance policy: Will this insure me in the event of a natural disaster?
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree


tr.v. en·sured, en·sur·ing, en·sures
To make sure or certain; insure: Our precautions ensured our safety. See Usage Note at assure.

[Middle English ensuren, from Anglo-Norman enseurer : Old French en-, causative pref.; see en-1 + Old French seur, secure, variant of sur; see sure.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ɛnˈʃʊə; -ˈʃɔː) or


vb (tr)
1. (may take a clause as object) to make certain or sure; guarantee: this victory will ensure his happiness.
2. to make safe or secure; protect
enˈsurer n
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ɛnˈʃʊər, -ˈʃɜr)

v.t. -sured, -sur•ing.
1. to secure or guarantee: This letter will ensure you a hearing.
2. to make sure or certain.
3. to make secure or safe, as from harm.
[1350–1400; Middle English < Anglo-French enseurer. See en-1, sure]
en•sur′er, n.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


1. 'assure'

If you assure someone that something is true or will happen, you tell them that it is definitely true or will definitely happen, often in order to make them less worried.

"I can assure you that neither of our two goalkeepers will be leaving," O'Leary said.
The government assured the public that there would be no increase in taxes.
2. 'ensure' and 'insure'

In British English, to ensure that something happens means to make certain that it happens.

His reputation was enough to ensure that he was always welcome.

In American English, this word is usually spelled insure.

I shall try to insure that your stay is a pleasant one.
3. 'insure'

Insure has another meaning. In both British and American English, if you insure your property, you pay money to a company so that if the property is lost, stolen, or damaged, the company will pay you a sum of money. In this meaning, the spelling is always insure, not 'ensure'.

Insure your baggage before you leave home.
Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011, 2012


Past participle: ensured
Gerund: ensuring

I ensure
you ensure
he/she/it ensures
we ensure
you ensure
they ensure
I ensured
you ensured
he/she/it ensured
we ensured
you ensured
they ensured
Present Continuous
I am ensuring
you are ensuring
he/she/it is ensuring
we are ensuring
you are ensuring
they are ensuring
Present Perfect
I have ensured
you have ensured
he/she/it has ensured
we have ensured
you have ensured
they have ensured
Past Continuous
I was ensuring
you were ensuring
he/she/it was ensuring
we were ensuring
you were ensuring
they were ensuring
Past Perfect
I had ensured
you had ensured
he/she/it had ensured
we had ensured
you had ensured
they had ensured
I will ensure
you will ensure
he/she/it will ensure
we will ensure
you will ensure
they will ensure
Future Perfect
I will have ensured
you will have ensured
he/she/it will have ensured
we will have ensured
you will have ensured
they will have ensured
Future Continuous
I will be ensuring
you will be ensuring
he/she/it will be ensuring
we will be ensuring
you will be ensuring
they will be ensuring
Present Perfect Continuous
I have been ensuring
you have been ensuring
he/she/it has been ensuring
we have been ensuring
you have been ensuring
they have been ensuring
Future Perfect Continuous
I will have been ensuring
you will have been ensuring
he/she/it will have been ensuring
we will have been ensuring
you will have been ensuring
they will have been ensuring
Past Perfect Continuous
I had been ensuring
you had been ensuring
he/she/it had been ensuring
we had been ensuring
you had been ensuring
they had been ensuring
I would ensure
you would ensure
he/she/it would ensure
we would ensure
you would ensure
they would ensure
Past Conditional
I would have ensured
you would have ensured
he/she/it would have ensured
we would have ensured
you would have ensured
they would have ensured
Collins English Verb Tables © HarperCollins Publishers 2011
ThesaurusAntonymsRelated WordsSynonymsLegend:
Verb1.ensure - make certain ofensure - make certain of; "This nest egg will ensure a nice retirement for us"; "Preparation will guarantee success!"
guarantee, vouch - give surety or assume responsibility; "I vouch for the quality of my products"
doom - make certain of the failure or destruction of; "This decision will doom me to lose my position"
make - assure the success of; "A good review by this critic will make your play!"
2.ensure - be careful or certain to do something; make certain of something; "He verified that the valves were closed"; "See that the curtains are closed"; "control the quality of the product"
proofread, proof - read for errors; "I should proofread my manuscripts"
check off, tick off, mark off, tick, check, mark - put a check mark on or near or next to; "Please check each name on the list"; "tick off the items"; "mark off the units"
control - verify by using a duplicate register for comparison; "control an account"
check - verify by consulting a source or authority; "check the spelling of this word"; "check your facts"
double-check - check once more to be absolutely sure
cross-check - check out conflicting sources; crosscheck facts, for example
cinch - make sure of
card - ask someone for identification to determine whether he or she is old enough to consume liquor; "I was carded when I tried to buy a beer!"
spot-check - pick out random samples for examination in order to ensure high quality
verify - confirm the truth of; "Please verify that the doors are closed"; "verify a claim"
ascertain, find out, learn, watch, determine, see, check - find out, learn, or determine with certainty, usually by making an inquiry or other effort; "I want to see whether she speaks French"; "See whether it works"; "find out if he speaks Russian"; "Check whether the train leaves on time"
cover - maintain a check on; especially by patrolling; "The second officer covered the top floor"
verify, control - check or regulate (a scientific experiment) by conducting a parallel experiment or comparing with another standard; "Are you controlling for the temperature?"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


1. make certain, guarantee, secure, make sure, confirm, warrant, certify Steps must be taken to ensure this never happens again.
2. protect, defend, secure, safeguard, guard, make safe The plan is aimed at ensuring the future of freshwater fish species.
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002


To render certain:
Informal: cinch.
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
يَتَأَكَّدُيَضْمَن، يُؤَمِّن
sikresørge for
assurercertifiers’assurer que
tryggja, ganga úr skugga um
bảo đảm


[ɪnˈʃʊəʳ] VTasegurar (that que)
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


[ɪnˈʃʊər] vt
[+ peace, stability, safety, security, survival] → assurer, garantir; [+ victory, success] → assurer
to ensure (that) ... (= make it certain) [thing] → garantir que ...
an attempt to ensure that there would not be a third attack → une tentative de garantir qu'il n'y aurait pas de troisième attaque
(= make sure that) [person] to ensure (that) ... → s'assurer que ...
You should ensure you do not miss the deadline → Assurez-vous de ne pas dépasser la date butoir.
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


vtsicherstellen; (= secure)sichern; will you ensure that I get a seat?sorgen Sie dafür, dass ich einen Platz bekomme?
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


[ɪnˈʃʊəʳ] vtgarantire, assicurare
to ensure that ... → assicurarsi che...
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(inˈʃuə) verb
to make sure. Ensure that your television set is switched off at night.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.


يَتَأَكَّدُ zajistit sikre sicherstellen διασφαλίζω asegurar, asegurarse varmistaa s’assurer que osigurati assicurare 保証する 보장하다 ervoor zorgen sørge for zapewnić assegurar гарантировать garantera ทำให้แน่ใจว่า garantiye almak bảo đảm 保证
Multilingual Translator © HarperCollins Publishers 2009
References in classic literature ?
The best intentions will not always ensure success.
Leave Frederica, therefore, to punish herself for the plague she has given you, by indulging that romantic tender-heartedness which will always ensure her misery enough, and come to London as soon as you can.
To ensure that your whole host may withstand the brunt of the enemy's attack and remain unshaken-- this is effected by maneuvers direct and indirect.
In the first place, I saw darkly what the nature of the conspiracy had been, how chances had been watched, and how circumstances had been handled to ensure impunity to a daring and an intricate crime.
The three fellows still abroad upon the island did not greatly trouble us; a single sentry on the shoulder of the hill was sufficient to ensure us against any sudden onslaught, and we thought, besides, they had had more than enough of fighting.
Her brother's recommendation was enough to ensure her favour; his judgement could not err.
AT a consultation, held between Colonel Winslow and Captain Murray, [of the New England forces, charged with the duty of exiling the Acadians,] it was agreed that a proclamation should be issued at the different settlements, requiring the attendance of the people at the respective posts on the same day; which proclamation should be so ambiguous in its nature that the object for which they were to assemble could not be discerned, and so peremptory in its terms as to ensure implicit obedience.
It would have been idle for me to have attempted resuming the interview so peremptorily terminated by Marnoo, who was evidently little disposed to compromise his own safety by any rash endeavour to ensure mine.
Their reply once ascertained, they could then discuss the mechanical means, and nothing should be wanting to ensure the success of this great experiment.
Their president, Barbicane, the promoter of the enterprise, having consulted the astronomers of the Cambridge Observatory upon the subject, took all necessary means to ensure the success of this extraordinary enterprise, which had been declared practicable by the majority of competent judges.
I had rather run any chance than your la'ship should do that."--"Why so?" says Sophia, smiling; "would not you, Honour, fire a pistol at any one who should attack your virtue?"--"To be sure, ma'am," cries Honour, "one's virtue is a dear thing, especially to us poor servants; for it is our livelihood, as a body may say: yet I mortally hate fire-arms; for so many accidents happen by them."--"Well, well," says Sophia, "I believe I may ensure your virtue at a very cheap rate, without carrying any arms with us; for I intend to take horses at the very first town we come to, and we shall hardly be attacked in our way thither.