From Longman Dictionary of Contemporary Englishthe final/supreme/ultimate sacrificethe final/supreme/ultimate sacrificeDIEthe act of dying while you are fighting for a principle or in order to help other people Captain Oates made the ultimate sacrifice in a bid to save his colleagues. → sacrifice
Examples from the Corpus
the final/supreme/ultimate sacrifice• This might appear to be the ultimate sacrifice on behalf of the colony, but all the bees in the colony are genetically related.• We felt that it was a great tribute to us and all our many comrades who made the supreme sacrifice.• You made the supreme sacrifice of your life for your work last night, so don't be shy about admitting it.• Also there, Captain Oates, the man who was to make the ultimate sacrifice in a bid to save his colleagues.• In that sense I suppose I am making the ultimate sacrifice.• These were people who showed courage, faith, and were an example to all by making the supreme sacrifice.• He evidently thought his life was so valuable that some one would surely save it even at the cost of the supreme sacrifice. 