vessel vs tube-shaped structure

vessel and tube-shaped structure both are nouns.

Word	Noun	Adjective	Verb	Adverb
vessel	Yes	No	No	No
tube-shaped structure	Yes	No	No	No

As nouns, tube-shaped structure is a hypernym of vessel; that is, tube-shaped structure is a word with a broader meaning than vessel:

Other hypernyms of vessel include tube.

vessel (noun)	tube-shaped structure (noun)
a craft designed for water transportation	(anatomy) any hollow cylindrical body structure
an object used as a container (especially for liquids)
a tube in which a body fluid circulates