What does "hold short" of a runway mean?

The term "hold short" of a runway specifically means that an aircraft is required to stop at a designated point before entering an active runway. This is crucial for maintaining safety and ensuring that aircraft do not inadvertently enter a runway that is occupied by another aircraft or in use for takeoff or landing operations.

When a pilot holds short, they remain at a specified location, often marked by signage or painted markings on the taxiway, waiting for clearance from air traffic control to proceed onto the runway. This procedure is essential in busy airspaces where multiple aircraft may be moving in close proximity, helping to prevent potential collisions and ensuring the smooth flow of air traffic.

The other options do not accurately describe the essential meaning of "hold short." Preparing for takeoff or taxing without stopping would imply an active intent to enter the runway, which contradicts the concept of holding short. Additionally, waiting for clearance to take off, while related, is not the same as holding short, as it involves being ready to depart rather than remaining stationary prior to runway entry.