Not good or enjoyable.
The weather was bad, so we stayed indoors.
Not of good quality.
This bread is bad; it's stale.
Very serious or severe.
He had a bad accident.
Not suitable or appropriate.
It's bad to be late for an important meeting.
Morally wrong.
Stealing is bad.
Behaving badly.
He's been bad all day.
Not skilled at something.
She's bad at math.
Harmful or damaging.
Smoking is bad for your health.
Painful or uncomfortable.
I have a bad knee.
Spoiled or rotten.
The milk has gone bad.
Annoyed or angry.
I'm in a bad mood today.
Feeling guilty or regretful.
I feel bad about forgetting your birthday.
Feeling ill.
I'm not feeling good; in fact, I feel bad.
Excellent, used in informal contexts.
That concert was bad!
Negative aspects or people.
There's a lot of bad in the world, but also a lot of good.
In a bad way.
She wanted to know how bad the damage was.