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verb en·sure \in-ˈshu̇r\

Simple Definition of ensure

  • : to make (something) sure, certain, or safe

Source: Merriam-Webster's Learner's Dictionary

Full Definition of ensure


  1. transitive verb
  2. :  to make sure, certain, or safe :  guarantee

Examples of ensure in a sentence

  1. 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

  2. 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

  3. 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

  4. They took steps to ensure the safety of the passengers.

  5. <regulations that ensure the wholesomeness of our food>

Origin of ensure

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

First Known Use: 1660

Synonym Discussion of 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>.

ENSURE Defined for Kids


verb en·sure \in-ˈshu̇r\

Definition of ensure for Students


  1. :  to make sure, certain, or safe :  guarantee <The crossing guard ensures our safety as we cross the street.>

Seen and Heard

What made you want to look up ensure? Please tell us where you read or heard it (including the quote, if possible).


a division or portion of a pool or whole

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