sibilant

When addressing Neo as “Mister Anderson” with a decidedly sibilant ess as robotic as it is arrogant, Weaving makes his character’s disaffected voice unsettling precisely because of how familiar it sounds.

In another passage, the players briefly whisper sibilants; a series of sliding glissandos in a double bass near the end, almost vocal, feels like a tiny, impeded aria.

They called out to each other in a flowing, sibilant tongue.

Even their language sets them apart from their neighbors: an invisible barrier of sibilants and elided vowels that always sounds like music to me.

The sibilant sound of the rattlesnake's tail has long been a movie cliché.