A more thorough explanation:

Definition: A pontifex (also known as a pontiff) was a member of the college of pontiffs, a group of priests who had control over religion in ancient Rome.

Example: Julius Caesar was appointed as the Pontifex Maximus, or the chief priest, in 63 BC.

This example illustrates how the term "pontifex" was used to refer to a member of the college of pontiffs, who held significant religious authority in ancient Rome. Julius Caesar's appointment as the Pontifex Maximus highlights the importance of this position in Roman society.