To deliberately remove the head of; to cut off (someone's) head.
To prevent (something) from being achieved.
To nullify
To reduce, to nothing, the strength of.
To overcome in battle or contest.
The act or instance of being defeated, of being overcome or vanquished; a loss.
Frustration (by prevention of success), stymieing; (law) nullification.
The act or instance of defeating, of overcoming, vanquishing.