1. to inform or notify in advance; to give prior notice or warning to
Usage: transitive verb; formal or technical register

Examples

• The company preinformed all employees about the upcoming restructuring.
• We were preinformed of the schedule change before the official announcement.
• The organizers preinformed participants about the new venue location.
• She preinformed her family that she would be arriving late.
• The hospital preinformed patients about the new check-in procedures.