insure
- 01 B2 Upper Intermediate
to buy a policy that pays you money if something bad happens to your property or health.
to arrange for compensation in the event of damage to or loss of property, or injury to or the death of someone, in exchange for regular payments.
Simple“It is important to insure your house against fire and flood damage.”
In context“The company decided to insure the entire fleet of delivery vehicles against theft and accidental damage to mitigate potential operational losses.”
UsageOften used with the preposition 'against' followed by the specific risk.
PitfallI need to insure that the door is locked. I need to ensure that the door is locked.Use 'insure' for financial protection and 'ensure' to mean 'make certain'.
- 02 C1 Advanced
to make sure that something will happen.
to make sure, certain, or safe; a variant spelling of 'ensure'.
Simple“Please insure that all the windows are closed before you leave the building.”
In context“The new safety protocols were designed to insure that no unauthorised personnel could access the laboratory after hours.”
UsageFollowed by a 'that' clause.
Teacher's tipIn modern English, 'ensure' is the standard spelling for this meaning; 'insure' is almost exclusively reserved for financial contexts.
insure vs ensure vs assure — Assure is for people, ensure is for outcomes, and insure is for financial protection.
“It is also a good idea to insure your bike the moment you arrive at university.”
First attested in c. 1440, as a variant of Middle English ensuren (from Anglo-Norman enseurer, itself from en- + seür (“sure”), probably influenced by Old French asseürer (“to assure”)); took on its particular sense of "make safe against loss by payment of premiums" in 1635, replacing assure. Doublet of ensure.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.