Curse (noun)

1. An appeal or prayer for evil or misfortune to befall someone or something.
2. Something that is regarded as evil or harmful.
3. An expletive used to express anger, frustration, or disappointment.
4. A cause of evil, harm, or annoyance.
5. A spell or incantation intended to bring evil upon someone or something.

Origin:

Middle english curs, from old english curs ("execration, curse, incantation"), from proto-germanic *kurzijaną ("to make a vow"), from proto-indo-european *ḱr̥s- ("to like, desire"), from *sker- ("to turn, bend"). cognate with german fluch ("curse"), dutch vloek ("curse"), norwegian norsk korse ("to curse"), and danish kurse ("to curse").

Examples:

1. She muttered a curse under her breath when she saw her car had a flat tire.
2. They put a curse on their enemies.
3. The old building was said to be under a curse.
4. Her losing streak was a curse on her luck.
5. The curse of the pharaohs was believed to have caused the death of many who entered the tomb.