How about, "
Safe Takeoff Distance is that distance required for takeoff that falls within the Balanced Field Length (Accelerate-Stop) calculations for the type, which take into consideration WAT limits, (Weight, Altitude, Temperature), runway gradient, wind and runway contamination" ?
You might be able to find something useful in the "
Takeoff Safety Training Aid" put out by the FAA some time ago. Give it a few moments to download.
Hope I didn't ruin anyone's fun.
I liked the gear-removal prevention distance but perhaps your interviewer will like
this one and hire you.