Elapsed time is the time that has passed. This can be a way of timing something or used for basic knowledge. This is also the amount of time between beginning and end of time.
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Elapsed time refers to how much time has passed from one period of time to the next. For example, if I left Miami for Atlanta at 3:00 am and arrived at 11:00 am, the elapsed time form when I left to when I arrived is 8 hours.