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1. Show displeasure, as after a performance or speech
   - hiss

1. A cry or noise made to express displeasure or contempt
   - hoot, Bronx cheer [N. Amer], hiss, raspberry, razzing [N. Amer], razz [N. Amer], snort, bird

1. Expressing disapproval
    
2. Exclamation used to startle or frighten

Derived forms: boos, booing, booed

Type of: call, condemn, cry, outcry, shout, vociferation, yell

Antonym: applaud

Encyclopedia: Boo