Death.
The time of day by which one must check out of a hotel, campground, hospital, parking garage, etc.
The time when one checks out (any sense).
The amount of time it takes to check out.
Death or failure.
An acute myocardial infarction, sometimes fatal, caused by the sudden occurrence of coronary thrombosis, which obstructs the blood supply to the heart and leads to necrosis of heart muscle tissue.