palpitation vs tremolo

palpitation and tremolo both are nouns.

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

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

palpitation: 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 palpitation include tremor.

palpitation (noun)	tremolo (noun)
a rapid and irregular heart beat	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