I. verb
to make a sibilant sound
he thought he heard a snake hiss
Synonyms: buzz, fizz, fizzle, sibilate, sizz, sizzle, swish, wheeze, whish, whisper, whiz, whoosh
II. noun
Synonyms: raspberry , bazoo, bird, boo, ||Bronx cheer, catcall, hoot, pooh, pooh-pooh, ||razz