Meaning & use
boo
An exclamation shouted to show disapproval or displeasure, especially at a performance or speech.
See it in a sentence
The crowd began to boo when the referee made the controversial call.
Fans shouted 'boo' as the visiting team walked onto the field.
A note on using this word
Boo is also informal slang for a romantic partner or close friend, a completely different, much newer sense.
Words with a similar meaning
Choose a synonym to suit the sentence. Meanings can overlap without being identical.
Words with an opposite meaning
Another way to use it
2. noun
An informal term for a person's romantic partner or close friend (slang).
She posted a photo with her boo on social media.
3. interjection
A sound made suddenly to surprise or frighten someone.
He jumped out from behind the door and yelled 'boo!'
Make it your own
Write a sentence using “boo”, then compare your use with the examples above.