exits
they are refereed to as doors 2 or 3 dependant on how many pairs of doors in total the a/c has:
e.g. the 737 - 800 has 4 pairs of doors
l1 and r1 at the front
l2 and r2 at row 15
l3 and r3 at row 16
l4 and r4 at the rear
this applies accross the 737 family.
the doors are not overhead but at mid cabin height