hushing vs hiss

hushing and hiss both are nouns.

Word	Noun	Adjective	Verb	Adverb
hushing	Yes	No	No	No
hiss	Yes	No	Yes	No

As nouns, hushing and hiss are synonyms defined as:

hushing and hiss: a fricative sound (especially as an expression of disapproval)

Other synonyms of hushing include fizzle, hissing, sibilation.

hushing (noun)	hiss (noun)
a fricative sound (especially as an expression of disapproval)	a cry or noise made to express displeasure or contempt
	a fricative sound (especially as an expression of disapproval)

hushing (verb)	hiss (verb)
	make a sharp hissing sound, as if to show disapproval
	express or utter with a hiss
	show displeasure, as after a performance or speech
	move with a whooshing sound