The term "sissing" generally refers to a hissing sound that is made by a reptile or a snake. However, there are several synonyms to this word which are used in different contexts and situations. Some of the common synonyms of "sissing" are whispering, rustling, murmuring, whistling, buzzing, humming, and swishing. A whispering sound is generally low and soft, while rustling refers to a sound made by the movement of leaves or paper. Murmuring is used to describe low and indistinct sounds made by humans, and whistling refers to a clear and sharp sound made by blowing air through pursed lips. Buzzing and humming generally refer to sounds made by insects or machines, while swishing refers to a sound made by the movement of air or water.