excreta vs piss

excreta and piss both are nouns.

Word	Noun	Adjective	Verb	Adverb
excreta	Yes	No	No	No
piss	Yes	No	Yes	No

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

excreta: waste matter (as urine or sweat but especially feces) discharged from the body
piss: liquid excretory product

excreta (noun)	piss (noun)
waste matter (as urine or sweat but especially feces) discharged from the body	informal terms for urination
	liquid excretory product

excreta (verb)	piss (verb)
	eliminate urine