boo Links Share URL Lookup “boo” at: Wikipedia Wiktionary Wordnik Dictionary.com Google noun a cry or noise made to express displeasure or contempt Synonyms hoot, Bronx cheer, hiss, raspberry, razzing, razz, snort, bird Less specific cry, outcry, call, yell, shout, vociferation verb show displeasure, as after a performance or speech Synonyms hiss Antonym applaud, clap, spat, acclaim Less specific condemn