Omnibus Clause Definition

noun
A portion of a writing that confers rights or duties upon one not specifically named, or property not specifically mentioned, as in: an automobile insurance policy provision that extends the policy’s coverage to any persons operating the motor vehicle, provided that the operator had the named insured’s permission, or a clause in a will that bequeaths all unspecified property, or property not known at the time of testation.
Webster's New World Law