flutter vs flicker

flutter and flicker both are nouns.

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

As nouns, flutter and flicker are synonyms defined as:

Other synonyms of flutter include waver.

As verbs, flutter and flicker are synonyms defined as:

Other synonyms of flutter include flitter, quiver, waver.

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

flutter (verb)	flicker (verb)
wink briefly	move back and forth very rapidly
beat rapidly	flash intermittently
move back and forth very rapidly	shine unsteadily
move along rapidly and lightly; skim or dart
flap the wings rapidly or fly with flapping movements