the.com/sibilance
the sound a sentence makes when it hisses instead of speaks.
means a hissing speech sound like s, sh, or z, and the poetic effect of clustering them for effect.
from from latin sibilare, to hiss or whistle, the same root that gave us sibilant snakes in old grammar books long before it slithered into poetry class.
snake testsay she sells seashells and feel it
mic problemaudio engineers de-ess vocals to tame it
poetic weaponpoe used it to make silence sound sinister