What is meant by 'clearance void time'?

Clearance void time refers to the specific timeframe within which a pilot must begin their departure after receiving a clearance. If the pilot does not depart within this designated time, the clearance becomes invalid. This concept is crucial for maintaining the flow of air traffic and ensuring safety. It helps air traffic control manage schedules efficiently and prevents pilots from holding clearances unnecessarily, which could lead to potential traffic conflicts or delays in the system. Understanding this timing is an essential part of pre-flight procedures and compliance with air traffic rules.