shrinkage vs decrement

shrinkage and decrement both are nouns.

Word	Noun	Adjective	Verb	Adverb
shrinkage	Yes	No	No	No
decrement	Yes	No	No	No

As nouns, decrement is a hypernym of shrinkage; that is, decrement is a word with a broader meaning than shrinkage:

Other hypernyms of shrinkage include decrease.

shrinkage (noun)	decrement (noun)
the act of stealing goods that are on display in a store	the amount by which something decreases
the amount by which something shrinks	a process of becoming smaller or shorter
process or result of becoming less or smaller