Delian healer is an epithet for zeus athena apollo oedipus
The answer is: Apollo.
You're question has already been asked. "Delian" refers to the location of Apollo's birth, which is the island of Delos. Apollo was also known as a "Healer." He was known as "the Healer" and brought both healing and prevention of disease and sickness to the world.
the correct answer would be apollo