Read the dictionary definition of brood. All definitions for this word.
1. the young of an animal cared for at one time
2. sit on (eggs)
1. Birds brood
2. The female covers the eggs
3. think moodily or anxiously about something
4. be in a huff; be silent or sullen
5. be in a huff and display one's displeasure
1. She is pouting because she didn't get what she wanted
6. hang over, as of something threatening, dark, or menacing
1. The terrible vision brooded over her all day long
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Merriam-Webster definition of brood