Transplant medicine

Two words in this list are pronounced identically at the end and spelt differently, and the difference is grammar rather than whim. Der Hirntod is a noun and ends in d, because it is built on der Tod, death. Hirntot is an adjective and ends in t, because it is built on tot, dead. German hardens every final d to a t in speech, so the ear cannot tell them apart; the inflected forms can. The noun gives des Hirntodes, with a voiced d you can hear; the adjective gives ein hirntoter Spender, with a t. So when you are unsure how to spell one of these, ask what the word is doing in the sentence: naming the event, or describing the person. The same test sorts out die Hirntoddiagnostik, which is built on the noun, from everything that describes a patient.