Here's why:
* Greek origin: The word "psychiatrist" comes from the Greek word "psyche" (meaning mind or soul) and "iatros" (meaning healer).
* Pronunciation shift: When the word entered English, the "p" at the beginning of "psyche" was often dropped in pronunciation, leading to the silent "p" in "psychiatrist".
So, while we spell it with a "p", we pronounce it as "si-kai-uh-trist".