flutter vs palpitate

flutter is a noun but palpitate is not a noun.

Word	Noun	Adjective	Verb	Adverb
flutter	Yes	No	Yes	No
palpitate	No	No	Yes	No

As verbs, flutter and palpitate are synonyms defined as:

flutter (noun)	palpitate (noun)
the act of moving back and forth
the motion made by flapping up and down
abnormally rapid beating of the auricles of the heart (especially in a regular rhythm); can result in heart block
a disorderly outburst or tumult

flutter (verb)	palpitate (verb)
wink briefly	beat rapidly
beat rapidly	shake with fast, tremulous movements
move back and forth very rapidly	cause to throb or beat rapidly
move along rapidly and lightly; skim or dart
flap the wings rapidly or fly with flapping movements