shush vs hush

shush is not a noun while hush is a noun.

Word	Noun	Adjective	Verb	Adverb
shush	No	No	Yes	No
hush	Yes	No	Yes	No

As verbs, hush is a hypernym of shush; that is, hush is a word with a broader meaning than shush:

Other hypernyms of shush include hush up, quieten, shut up, silence, still.

shush (noun)	hush (noun)
	(poetic) tranquil silence

shush (verb)	hush (verb)
silence (someone) by uttering `shush!'	become quiet or still; fall silent
	cause to be quiet or not talk
	run water over the ground to erode (soil), revealing the underlying strata and valuable minerals
	wash by removing particles
	become quiet or quieter