excretion vs excrement

excretion and excrement both are nouns.

Word	Noun	Adjective	Verb	Adverb
excretion	Yes	No	No	No
excrement	Yes	No	No	No

As nouns, excretion and excrement are synonyms defined as:

excretion and excrement: waste matter (as urine or sweat but especially feces) discharged from the body

Other synonyms of excretion include body waste, excreta, excretory product.

excretion (noun)	excrement (noun)
the bodily process of discharging waste matter	waste matter (as urine or sweat but especially feces) discharged from the body
waste matter (as urine or sweat but especially feces) discharged from the body