The "ssh" sound is an example of something that would be described as a sibilant.
The "sssh" sound is an example of a sibilant.
The sibilant consonants; a sibilant bird call.
Origin of sibilant
- Latin sībilāns sībilant- present participle of sībilāre to hiss
From American Heritage Dictionary of the English Language, 5th Edition
- From Latin sÄ«bilÄns, present active participle of sÄ«bilÅ (“I hiss").