A more thorough explanation:

Definition: A phrase commonly used in legal practice to refer to a specific date or place by approximation. It is often used in civil or criminal complaints or legal documents that create obligations or protections for a party. The phrase expands the accuracy or coverage of a statement without pointing to an exact date or place that would be more easily challenged.

When used to describe a location, "on or about" means anywhere and everywhere on, but not outside of, the specific area in question. For example, a contract may allocate risk against loss by fire for anything "on or about said leased premises." Similarly, when used in a complaint, it could describe the location of an occurrence as "on or about the corner of Main and Chestnut Streets."

When used to describe a date, it means generally in the time around the specified date. For purposes of the pleading requirement that a petition must give fair and adequate notice of the facts forming the basis of a claim, the term "on or about" means a date of approximate certainty, with a possible variance of a few days. Although this is generally sufficient where a particular date is not material, it is not sufficient where the statute of limitations is involved.

For example, the precise date of the commission of the crime of burglary is not essential to the offense, and the use of the expression "on or about" a certain date in charging this offense is correct. However, the case against the accused is only sufficiently proved if it is shown that the crime was committed and prosecuted within the time limited by the statute of limitations for this offense.

Examples:

• A lease agreement may state that the tenant is responsible for any damage to the property "on or about said leased premises."
• A complaint may allege that a crime was committed "on or about the night of June 15th."
• A contract may specify that payment is due "on or about the 1st of the month."

These examples illustrate how the phrase "on or about" is used to provide an approximation of a time or place without being too specific. It allows for some flexibility while still conveying the necessary information.