shaky vs unstable

shaky and unstable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
shaky	No	Yes	No	No
unstable	No	Yes	No	No

shaky (adjective)	unstable (adjective)
not secure; beset with difficulties	lacking stability or fixity or firmness
inclined to shake as from weakness or defect	subject to change; variable
vibrating slightly and irregularly; as e.g. with fear or cold or like the leaves of an aspen in a breeze	suffering from severe mental illness
	disposed to psychological variability
	highly or violently reactive
	affording no ease or reassurance