Green’s Dictionary of Slang

1. (UK Und.) a pickpocketing expedition.

1865

Leaves from Diary of Celebrated Burglar 101/1: The best thing they could do was to take a ‘run out’ and see if they were lucky enough to ‘pull a bag’ or two off.

2. (also run-out) an escape, an evasion, thus v. take a run-out, to escape, to absent oneself.

1930		D. Hammett Maltese Falcon (1965) 389: ‘Thursby was Dixie’s bodyguard and he took the run-out with him when Dixie got in wrong with the rest of the boys over some debts’.
1953		J. Thompson Savage Night (1991) 7: If The Man had been afraid of a runout, I wouldn’t have been here.