A position in a game is unsafe for player if the person who plays next (player ) can win. Every unsafe position can be made safe by at least one move.
Unsafe
See also
Game, SafeExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Unsafe." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Unsafe.html