(set phrase, of a contest) That will continue until one of the contestants dies.
The two gladiators fought to the death.
(idiomatic) To the utmost degree.
Source: en.wiktionary.orgA revolution is not a trail of roses.... A revolution is a fight to the death between the future and the past. Fidel Castro
I do not agree with what you have to say, but I'll defend to the death your right to say it. Voltaire
Defoe says that there were a hundred thousand country fellows in his time ready to fight to the death against popery, without knowing whether popery was a man or a horse. William Hazlitt
If any foreign minister begins to defend to the death a 'peace conference', you can be sure his government has already placed its orders for new battleships and airplanes. Joseph Stalin
I disapprove of what you say, but I will defend to the death your right to say it. Evelyn Beatrice Hall
A warrior fights to the death. Klingon Proverb