Final answer:
The term cancer was first used by Hippocrates, the Greek physician known as the father of Western medicine. He was the first to describe diseases, including cancer, as having natural causes.
Step-by-step explanation:
The word cancer was first used by the Greek physician Hippocrates (460-370 BC), who is considered the "father of Western medicine." Hippocrates and his successors wrote the Hippocratic Corpus, which includes some of the oldest surviving medical books. He believed that diseases, including what we today refer to as cancer, had natural causes arising from within patients or their environments, which he studied in contrast to supernatural beliefs.
Hippocrates's approach to medicine was empirical and based on clinical observation, a significant departure from prior traditions. His contributions to medicine are foundational, and his name is also associated with the Hippocratic Oath, an ethical code still used to this day, though in a modern form, by new physicians.