hush vs shush

hush is a noun but shush is not a noun.

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

As verbs, shush is a hyponym of hush; that is, shush is a word with a more specific, narrower meaning than hush:

Other hyponyms of hush include calm down, lull, shout down, gag, muzzle.

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

hush (verb)	shush (verb)
become quiet or still; fall silent	silence (someone) by uttering `shush!'
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