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verb, in·sure \in-ˈshu̇r\

Simple Definition of insure

  • : to buy insurance for (something, such as property or health)

  • : to provide insurance for (something, such as property or health); also : to provide (someone) with insurance

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of insure


  1. transitive verb
  2. 1 :  to provide or obtain insurance on or for

  3. 2 :  to make certain especially by taking necessary measures and precautions

  4. intransitive verb
  5. :  to contract to give or take insurance

Examples of insure in a sentence

  1. He found the language not obscene … but did find it intentionally disruptive, and held that school officials had the right to insure that a high-school assembly proceed in an orderly manner, without hoots and howls and all that snickering. —William Safire, New York Times Magazine, 24 Aug. 1986

  2. … his sudden fame probably insured a backlash. —Calvin Tomkins, New Yorker, 6 Dec. 1982

  3. 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

  4. We insured our house against fire and flood damage.

  5. I found a company that will insure my car for less than I've been paying.

  6. This policy will insure your car against theft.

  7. She had difficulty finding a company that would insure her.

  8. They take great care to insure the safety and security of their home.

  9. We hope that careful planning will insure success.

Origin of insure

Middle English, to assure, probably alteration of assuren

First Known Use: 1635

Synonym Discussion of insure

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>.

INSURE Defined for Kids


verb in·sure \in-ˈshu̇r\

Definition of insure for Students


  1. 1 :  to give or get insurance on or for <I insured my car.>

  2. 2 :  to make certain <I want to insure your safety.>

insurer noun

Law Dictionary


verb in·sure \in-ˈshu̇r\

Legal Definition of insure


  1. transitive verb
  2. :  to assure against a loss by a contingent event on certain stipulated conditions or at a given rate of premium :  give, take, or procure insurance on or for
  3. intransitive verb
  4. :  to contract to give insurance :  underwrite; also :  to procure or effect insurance

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