1boo 
/ˈbu:/ noun
plural boos /ˈbu:/ noun 1 [count] : a sound that people make to show they do not like or approve of someone or something
▪ A chorus of boos was heard after the shot missed the goal. ▪ The announcement was greeted by/with a mixture of boos and cheers. 2 [noncount] informal : any sound at all — usually used in negative statements ▪ He never said boo [=he never said anything], so I didn't even know he was there. ◊A person who (US) wouldn't say boo or (Brit) wouldn't say boo to a goose is very quiet and shy.
▪ A chorus of boos was heard after the shot missed the goal. ▪ The announcement was greeted by/with a mixture of boos and cheers.
