in this passage, what does "breakout" mean? That was the last car in President Johnson's first motorcade; with its hair-raising arrival from Parkland, the Youngblood breakout, as it might he called, was complete. Parkland didn't know it, though. Most of the agents and aides in the emergency area were under the impression that the group that had begun the grand tour of Texas at San Antonio International Airport the day before was intact.