excrement vs feces

excrement and feces both are nouns.

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

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

excrement: waste matter (as urine or sweat but especially feces) discharged from the body
feces: solid excretory product evacuated from the bowels

excrement (noun)	feces (noun)
waste matter (as urine or sweat but especially feces) discharged from the body	solid excretory product evacuated from the bowels