dejection vs excretion

dejection and excretion both are nouns.

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

As nouns, excretion is a hypernym of dejection; that is, excretion is a word with a broader meaning than dejection:

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

Other hypernyms of dejection include body waste, excrement, excreta, excretory product.

dejection (noun)	excretion (noun)
a state of melancholy depression	the bodily process of discharging waste matter
solid excretory product evacuated from the bowels	waste matter (as urine or sweat but especially feces) discharged from the body