The term APB PART OF is composed of three words: ALL (3 letters), ALERT (5 letters), and RADIO (5 letters). All together, they refer to the term 'All Points Bulletin, ' which is a broadcast issued from any American law enforcement agency to its officers. An APB is typically used to ALERT officers to be on the lookout for a specific person or vehicle. The term 'All Points Bulletin' is derived from the fact that the broadcast is sent out to all points, meaning all areas within the jurisdiction of the issuing agency.