Nolo's Plain-English Law Dictionary

Act Of God

An extraordinary and unexpected natural event, such as a hurricane, tornado, earthquake, tsunami, or even the sudden death of a person. An act of God may be a defense against liability for injuries or damages; insurance policies often exempt coverage for damage caused by acts of God. Under the law of contracts, an act of God often serves as a valid excuse if one of the parties to the contract is unable to fulfill his or her duties -- for instance, completing a construction project on time.
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