How does the term "Waterloo" function in a figurative sense in modern language?

The term "Waterloo" in modern language carries the connotation of a decisive defeat, stemming from its historical context. The Battle of Waterloo, fought in 1815, was a pivotal moment in European history where Napoleon Bonaparte faced his ultimate defeat, leading to the end of his reign. This historical significance has allowed the term to evolve into a metaphor used to signify any significant setback or defeat faced by an individual or group.

When someone refers to a "Waterloo," they evoke the weight of a decisive moment that leads to a downfall, much like Napoleon's collapse after the battle. This usage encapsulates the essence of a crushing loss or a turning point that has severe implications, underscoring the lasting impact of that historical event on language and idiom.