insure

verb (used with object), in·sured, in·sur·ing.

1. to guarantee against loss or harm.
2. to secure indemnity to or on, in case of loss, damage, or death.
3. to issue or procure an insurance policy on or for.
4. ensure(defs 1–3).

verb (used without object), in·sured, in·sur·ing.

5. to issue or procure an insurance policy.

verb

1. (often foll by against) to guarantee or protect (against risk, loss, etc)we insured against disappointment by making an early reservation
2. (often foll by against) to issue (a person) with an insurance policy or take out an insurance policy (on)his house was heavily insured against fire; after all his car accidents the company refuses to insure him again
3. another word (esp US) for ensure (def. 1), ensure (def. 2)