Bad (adjective)

1. Not good in quality, or not of a high standard.
2. Not functioning or performing well.
3. Not suitable or appropriate.
4. Morally wrong or evil.
5. Feeling ill or in pain.

Origin:

Derived from old english 'baed' meaning 'bad, wicked'.

Examples:

1. The food was bad.
2. The car is running bad.
3. That was a bad decision.
4. He has a bad reputation.
5. I have a bad headache.