bedpan vs vessel

bedpan and vessel both are nouns.

Word	Noun	Adjective	Verb	Adverb
bedpan	Yes	No	No	No
vessel	Yes	No	No	No

As nouns, vessel is a hypernym of bedpan; that is, vessel is a word with a broader meaning than bedpan:

bedpan: a shallow vessel used by a bedridden patient for defecation and urination
vessel: an object used as a container (especially for liquids)

bedpan (noun)	vessel (noun)
a shallow vessel used by a bedridden patient for defecation and urination	a craft designed for water transportation
	an object used as a container (especially for liquids)
	a tube in which a body fluid circulates