hiss
A sibilant sound, such as that made by a snake or escaping steam; an unvoiced fricative.
Other meanings
An expression of disapproval made using such a sound.
Word history
From Middle English "hissen".
Where this comes from
This definition is adapted from “hiss” on Wiktionary, by its contributors, published under CC BY-SA 4.0. This page is published under the same licence.