assure

assure — verb

1. to speak firmly and confidently to a worried listener so they stop having doubts

1.verbtransitiveB2
Definition

to speak firmly and confidently to a worried listener so they stop having doubts about a fact or about something that will happen.

Example

Dr. Nikolai assured Noa that the test results were completely normal.

assure + somebody + that-clause

The pilot assured the nervous passengers of a smooth landing in Taipei.

assure + somebody + of + noun

Common collocations
  • assure somebody that
  • assure somebody of something
  • I can assure you
  • assure repeatedly
  • hastily assure
Synonyms
  • reassure

    stronger focus on calming someone who is already worried

  • promise

    more about a personal commitment than confirming a fact

  • convince

    succeeds in changing the listener's mind, not just stating something firmly

Antonyms
  • warn

    tells someone of danger rather than calming their doubts

Grammar Patterns

assure + somebody + (that)-clause

assure + somebody + of + noun

assure + somebody + "direct speech"

Usage Note

Object must be a person or group, never a thing. Distinguish from sense 2 (MAKE CERTAIN), where the object is the outcome itself, not a listener.

Common Mistakes

He assured that the train was on time.
He assured us that the train was on time.
assure in this sense always needs a person as direct object.
She assured to me that everything was fine.
She assured me that everything was fine.
no preposition before the person.

2. to do something that guarantees a future result will definitely happen, such as

2.verbtransitiveC1
Definition

to do something that guarantees a future result will definitely happen, such as a victory, a place, or a supply.

Example

Two early goals from Bram assured the team a place in the final.

assure + somebody + noun (guaranteed outcome)

Strong sales in Asia have assured the company's profits for another year.

assure + noun (future result)

Common collocations
  • assure success
  • assure victory
  • assure a place
  • assure profits
  • be assured of
Synonyms
  • guarantee

    more common and slightly less formal in everyday writing

  • secure

    emphasises obtaining something through effort

  • ensure

    wider use; assure suggests a stronger, almost absolute result

Antonyms
  • jeopardise

    puts a future result at risk rather than locking it in

Grammar Patterns

assure + noun (outcome)

assure + somebody + noun

Usage Note

Subject is typically a cause, action, or quality (not a speaker). Object is the outcome itself. Often appears in the passive ("victory was assured"). Distinguish from sense 1, where the object is always a person.

Common Mistakes

He assured me victory by training hard.
His hard training assured victory.
in this sense, the cause is the subject; the listener is not the focus.

3. (used by British insurance firms) to formally promise, in exchange for regular s

3.verbtransitive
Definition

(used by British insurance firms) to formally promise, in exchange for regular small contributions, that money will be paid out when somebody dies — usually to that person's family.

Example

Mr. Patel had assured his life for £200,000 to protect his three children.

assure + one's life + for + amount

All staff at the factory are assured against accidental death at work.

passive: be assured against + risk

Common collocations
  • assure one's life
  • assure against death
  • assured sum
  • life assurance
Synonyms
  • insure

    the standard modern word, used for all kinds of risks (cars, homes, lives)

  • underwrite

    technical term for an insurance company taking on a risk

Grammar Patterns

assure + somebody/something

assure + somebody + against + noun

Usage Note

Almost only British, almost only in life-insurance contracts. Americans and most modern British speakers use "insure" instead. Often seen in the fixed phrase "assured sum" or in company names ending in "Life Assurance".

Common Mistakes

I assured my new car last week.
I insured my new car last week.
assure for property/cars sounds wrong; use insure.

Word family

Synonym discussion

Sense: verb/1

These four verbs sound similar but do different jobs. "Assure" needs a person as object — you assure someone that something is true, usually to calm worry: "The doctor assured Noa the results were normal." "Reassure" is stronger and warmer; it implies the listener was clearly anxious and is now calmed: "He reassured the frightened child." "Ensure" takes a thing or outcome, never a person, and means to make sure something happens: "Lock the door to ensure your safety." "Insure" is purely financial — paying a company so they cover a loss: "I insured my new car." In British insurance contracts, "assure" can replace "insure", but only for life cover. Quick rule: assure people, ensure outcomes, insure property and lives, reassure the worried.

assure ↗ensure ↗insure ↗reassure ↗

Common collocations

Nouns

  • assure somebody
  • assure success
  • assure victory
  • assure a place

Adverbs

Phrases

  • I can assure you
  • rest assured
  • you may be assured
  • let me assure you

Prepositions

  • assure of (something)
  • assure against (a risk)

Etymology

LatinOld FrenchMiddle EnglishEnglish

Assure entered English in the 1300s through Old French "asseurer", meaning to make safe or give confidence. The Old French word grew from Latin "ad-" (to) plus "securus" (free from care), the same Latin root that gives us "secure" and "sure". So at heart, to assure someone is literally to bring them toward feeling safe. The insurance sense developed later, in the 1500s, when promising someone safety became a paid business arrangement.