ureter vs duct

ureter and duct both are nouns.

Word	Noun	Adjective	Verb	Adverb
ureter	Yes	No	No	No
duct	Yes	No	No	No

As nouns, duct is a hypernym of ureter; that is, duct is a word with a broader meaning than ureter:

ureter: either of a pair of thick-walled tubes that carry urine from the kidney to the urinary bladder
duct: a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance

Other hypernyms of ureter include canal, channel, epithelial duct.

ureter (noun)	duct (noun)
either of a pair of thick-walled tubes that carry urine from the kidney to the urinary bladder	an enclosed conduit for a fluid
	a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance
	a continuous tube formed by a row of elongated cells lacking intervening end walls