AKAWN

Always On.

No it’s not a US vs UK thing.

https://docs.microsoft.com/en-us/sql/sql-server/editions-and-components-of-sql-server-version-15?view=sql-server-ver15#RDBMSHA

https://docs.microsoft.com/en-us/sql/database-engine/availability-groups/windows/always-on-availability-groups-sql-server?view=sql-server-ver15

Also a note on the abbreviation AG: