twinkling vs heartbeat

twinkling and heartbeat both are nouns.

Word	Noun	Adjective	Verb	Adverb
twinkling	Yes	Yes	No	No
heartbeat	Yes	No	No	No

As nouns, twinkling and heartbeat are synonyms defined as:

twinkling and heartbeat: a very short time (as the time it takes the eye to blink or the heart to beat)

Other synonyms of twinkling include blink of an eye, flash, instant, jiffy, New York minute, split second, trice, wink.

twinkling (noun)	heartbeat (noun)
a very short time (as the time it takes the eye to blink or the heart to beat)	an animating or vital unifying force
	the rhythmic contraction and expansion of the arteries with each beat of the heart
	a very short time (as the time it takes the eye to blink or the heart to beat)

twinkling (adjective)	heartbeat (adjective)
shining intermittently with a sparkling light