Fear (noun)

1. An unpleasant emotion caused by the belief that someone or something is dangerous, likely to cause pain, or a threat.
2. The likelihood of something unwelcome happening.

Origin:

Old english fǣr, fēr, of germanic origin; related to dutch gevaar and german gefahr.

Examples:

1. He felt a sense of fear when he saw the stranger in the dark alley.
2. The fear of failure can sometimes hold us back from trying new things.
3. There is a fear that the current political instability will lead to violence.
4. Many people have a fear of flying.
5. The high crime rate is a major fear among residents of the city.