Which term refers to an omen or prophecy?

The term that refers to an omen or prophecy is "augury." In ancient Roman and Greek cultures, augury specifically denoted the practice of interpreting the behavior of birds to predict the future or ascertain divine guidance. This method of divination was deeply intertwined with religious and cultural beliefs, making augury a significant aspect of understanding fate and prophecy in works like "Oedipus Rex."

In contrast, "auspice" typically relates to a favorable omen or a sign that indicates good fortune, which is a narrower definition than augury. "Foreshadowing" is a literary device that hints at events to come within a narrative, but it doesn’t imply a prophetic or divine element as augury does. "Anticipation" refers to the act of expecting or predicting something but lacks the connotation of divine or supernatural insight associated with augury. Thus, "augury" is the most accurate term to denote an omen or prophecy in the context of the question.