shaking vs shakiness

shaking and shakiness both are nouns.

Word	Noun	Adjective	Verb	Adverb
shaking	Yes	No	No	No
shakiness	Yes	No	No	No

As nouns, shaking and shakiness are synonyms defined as:

Other synonyms of shaking include palpitation, quiver, quivering, trembling, vibration.

shaking (noun)	shakiness (noun)
the act of causing something to move up and down (or back and forth) with quick movements	the quality of being unstable and insecure
a shaky motion	a shaky motion