1To get angry; to get mad; to lose one's temper. The everyday intransitive usage, common in both speech and writing.
彼はちょっとしたことですぐ怒る。
He gets angry easily over little things.
そんな言い方をされたら誰でも怒るよ。
Anyone would get angry if you talked to them like that.
そんなに怒らないで、話を聞いてください。
Don't be so angry — please listen to what I'm saying.
約束を破られて、彼女は本気で怒っている。
She's genuinely angry because her promise was broken.
2To scold; to tell someone off. This transitive sense is overwhelmingly used in the passive form (〜に怒られる), meaning 'to be scolded by ~'.
宿題を忘れて、先生に怒られた。
I forgot my homework and got scolded by the teacher.
また遅刻したら、お母さんに怒られるよ。
If you're late again, Mom will tell you off.
先生はふざけていた生徒を厳しく怒った。
The teacher strictly scolded the students who were fooling around.