On or about
Near; approximately; without significant variance from an agreed date.
The phrase on or about is used to avoid being bound to a more precise statement than is required by law. For example, when an individual seeks to purchase a home, the date when the transaction is closed and the legal title and possession are transferred from seller to buyer is ordinarily scheduled on or about a particular date. The phrase is used to indicate that the parties recognize the fact that, although the exact date might not be convenient for both of them, the transaction should be completed as close to that date as is practicable.
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Law Library - American Law and Legal InformationFree Legal Encyclopedia: Notice of abandonment to Ordinary resolution