AA 2917 then UA 3376 at O'Hare
Miami → Chicago → St Louis
Timetable, Chicago time
18:23AA 2917 from Miami at the gate
11:00UA 3376 to St Louis leaves the gate
16 h 37 apart on the timetable, overnight
UA 3376 leaves 16 h 37 after AA 2917 arrives on the timetable: more than half a day, so not a connection we count.