decrement vs wastage

decrement and wastage both are nouns.

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

As nouns, wastage is a hyponym of decrement; that is, wastage is a word with a more specific, narrower meaning than decrement:

Other hyponyms of decrement include decay, decline, decline, diminution, desensitisation, desensitization, narrowing, slippage.

decrement (noun)	wastage (noun)
the amount by which something decreases	anything lost by wear or waste
a process of becoming smaller or shorter	the process of wasting