harbinger
n.n. something that is a sign of a future event. It is often used to describe a person or thing that shows that a big change is coming.
n. a person or thing that is a sign of something about to happen. Often used in a literary or formal context to indicate a forewarning of a significant change or event.
The early frost was a harbinger of a harsh winter.
The sudden increase in interest rates was seen as a harbinger of a coming economic recession.
In many ancient myths, the appearance of a specific animal or celestial event serves as a harbinger of the hero's final trial or the kingdom's impending doom.
Originally, a person sent in advance to arrange lodgings. From Middle English herberjour, herbergeour, from Old French herbergeor (French hébergeur), from herbergier (“to set up camp; to shelter; to take shelter”) + -or (suffix forming agent nouns), from Old High German heribergan, ultimately from Proto-West Germanic *harjabergu (“army camp, shelter”). Compare German Herberge, Italian albergo, Dutch herberg, English harbor. More at here, borrow.