<p><strong>Verb:</strong></p><ul><li>(Used without object) To make or emit a sharp sound like that of the letter s prolonged, as a snake does, or as steam does when forced under pressure through a small opening.</li><li>To express disapproval or contempt by making this sound: The audience hissed when the actor forgot his lines.</li><li>(Used with object) To express disapproval of by hissing: The audience hissed the controversial play.</li><li>To silence or drive away by hissing (usually followed by away, down, etc.): They hissed down the author when he tried to speak.</li><li>To utter with a hiss.</li></ul><p><strong>Noun:</strong></p><ul><li>A hissing sound, especially one made in disapproval.</li></ul>