excretion vs wormcast

excretion and wormcast both are nouns.

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

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

excretion: waste matter (as urine or sweat but especially feces) discharged from the body
wormcast: cylindrical mass of earth voided by a burrowing earthworm or lugworm

excretion (noun)	wormcast (noun)
the bodily process of discharging waste matter	fossil trail of a worm
waste matter (as urine or sweat but especially feces) discharged from the body	cylindrical mass of earth voided by a burrowing earthworm or lugworm