AA 6332 then UA 3376 at O'Hare
St Louis → Chicago → St Louis
Timetable, Chicago time
14:56AA 6332 from St Louis at the gate
11:00UA 3376 to St Louis leaves the gate
20 h 04 apart on the timetable, overnight
UA 3376 leaves 20 h 04 after AA 6332 arrives on the timetable: more than half a day, so not a connection we count.