Hissing was a sibillant sound made by some lifeforms.
In 2369, William T. Riker sustained a deep cut while feeding Spot, who he described as "a hissing ball of fur coming at my face". (TNG: "Timescape")
Hissing could also be made by escaping vapor. According to Quark, defective anodyne circuits made a hissing sound. (DS9: "The Ascent")