AA 642 then UA 5783 at O'Hare
Dallas-Fort Worth → Chicago → Nashville
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
12:23UA 5783 to Nashville leaves the gate
23 h 13 apart on the timetable, overnight
UA 5783 leaves 23 h 13 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.