Nemeses

The farmer's nemeses were the locusts that ate his crops year after year.

The city's nemeses, potholes, made for a bumpy and frustrating commute.

Her mother was her nemeses when it came to fashion choices.

Impulsive buying was one of her nemeses that resulted in a financial crisis.

The scientist believed that time was the ultimate nemeses, always ticking away and limiting his ability to achieve his goals.