In genealogy, the abbreviation ABT stands for about. It is commonly used in family trees and genealogical records to indicate that the date or information provided is not exact but is estimated or approximated.
For example, if a birth year is listed as ABT 1800, it suggests that the individual was born around the year 1800, but the exact year might not be known. This can occur for various reasons, such as incomplete records, oral histories, or uncertainties in documentation.
Using ABT helps genealogists convey the idea that while certain details are not precisely known, they can still provide valuable context for understanding family histories and timelines.