shaking vs tremolo

shaking and tremolo both are nouns.

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

As nouns, tremolo is a hyponym of shaking; that is, tremolo is a word with a more specific, narrower meaning than shaking:

shaking: a shaky motion
tremolo: (music) a tremulous effect produced by rapid repetition of a single tone or rapid alternation of two tones

Other hyponyms of shaking include tremor.

shaking (noun)	tremolo (noun)
the act of causing something to move up and down (or back and forth) with quick movements	vocal vibrato especially an excessive or poorly controlled one
a shaky motion	(music) a tremulous effect produced by rapid repetition of a single tone or rapid alternation of two tones