What does "insure" mean?

Insure: Specifically, to secure against a loss by a contingent event, on certain stipulated conditions, or at a given rate or premium; to give or to take an insurance on or for; as, a merchant insures his ship or its cargo, or both, against the dangers of the sea; goods and buildings are insured against fire or water; persons are insured against sickness, accident, or death; and sometimes hazardous debts are insured.