rheum vs emission

rheum and emission both are nouns.

Word	Noun	Adjective	Verb	Adverb
rheum	Yes	No	No	No
emission	Yes	No	No	No

As nouns, emission is a hypernym of rheum; that is, emission is a word with a broader meaning than rheum:

rheum: a watery discharge from the mucous membranes (especially from the eyes or nose)
emission: a substance that is emitted or released

Other hypernyms of rheum include discharge.

rheum (noun)	emission (noun)
a watery discharge from the mucous membranes (especially from the eyes or nose)	the act of emitting; causing to flow forth
	the occurrence of a flow of water (as from a pipe)
	the release of electrons from parent atoms
	any of several bodily processes by which substances go out of the body
	a substance that is emitted or released