A reader writes:
“Using ensure and assure interchangeably bothers me.”
Maybe using assure upsets the stomach?
Seriously, though, it bothers us, too. Plus, there’s the related word insure. So, let’s explore …
Many thesauri list these as synonyms for each other, so that helps to confuse us further … In general, to assure is to lend confidence, to ensure is to confirm, and to insure is to indemnify (as with an insurance policy) – and insure may have legal implications.
As per the AP Stylebook: Use ensure to mean guarantee: Steps were taken to ensure accuracy. Use insure for references to insurance: The policy insures his life.
Another source adds: Assure most commonly means “to remove doubt about, to guarantee, to set one’s mind at rest.” It is a verbal statement of certainty.
YourDictionary.com presents helpful tips:
To help you remember when to use each word, keep the following three hints in mind:
- You assure a person.
- You insure your car.
- You ensure everything else.
assure. verb (used with object), -sured, -sur⋅ing.
- to declare earnestly to; inform or tell positively; state with confidence to: She assured us that everything would turn out all right.
- to cause to know surely; reassure: He assured himself that no one was left on the bus.
- to pledge or promise; give surety of; guarantee: He was assured a job in the spring.
- to make (a future event) sure: This contract assures the company’s profit this month.
- to secure; render safe or stable: to assure a person’s position.
- to give confidence to; encourage.
- Chiefly British. to insure, as against loss.
ensure. verb (used with object), -sured, -sur⋅ing.
- to secure or guarantee: This letter will ensure you a hearing.
- to make sure or certain: measures to ensure the success of an undertaking.
- to make secure or safe, as from harm.
insure. verb (used with object)
- to guarantee against loss or harm.
- to secure indemnity to or on, in case of loss, damage, or death.
- to issue or procure an insurance policy on or for.
- see ensure (defs. 1–3).
insure. verb (used without object)
- to issue or procure an insurance policy.