shrink vs die down

shrink is a noun but die down is not a noun.

Word	Noun	Adjective	Verb	Adverb
shrink	Yes	No	Yes	No
die down	No	No	Yes	No

As verbs, die down is a hyponym of shrink; that is, die down is a word with a more specific, narrower meaning than shrink:

Other hyponyms of shrink include atrophy, blast, die back, dry up, mummify.

shrink (noun)	die down (noun)
a physician who specializes in psychiatry

shrink (verb)	die down (verb)
become smaller or draw together	suffer from a disease that kills shoots
reduce in size; reduce physically	become progressively weaker
wither, as with a loss of moisture
decrease in size, range, or extent
draw back, as with fear or pain