A technical decision is a term used in boxing when a fight has to be stopped because of a headbutt.
In boxing fights, referees have to pay deep attention to the action going on between the fighters, especially when the two combatants are fighting close to each other. This is because, in the case of a cut, the referee must decide whether the cut was caused by a punch or by a head collision. Only the referee can make that decision.
Most head collisions in boxing are probably unintentional, especially when both boxers are trying for a knockout, many times getting involved in close range fights. If a boxer intentionally butts an opponent's head, this is considered a flagrant foul that could result in disqualification of the offender.
In the case of a cut to the head, it is the referee's responsibility of taking the injured boxer to a medical doctor seated at ringside as many times as the referee thinks necessary, regardless of the referee's decision of the cut being provoked by a punch or not. When the doctor tells the referee that the combatant cannot go on, then the referee must stop the fight. If the referee decided that the cut was caused by a punch, then the other boxer wins by technical knockout. If the referee decides it was produced by a collision, then the judges at ringside must hand over their scorecards, and the fighter ahead on points wins by technical decision.