cestode vs taenia

cestode and taenia both are nouns.

Word	Noun	Adjective	Verb	Adverb
cestode	Yes	No	No	No
taenia	Yes	No	No	No

As nouns, taenia is a hyponym of cestode; that is, taenia is a word with a more specific, narrower meaning than cestode:

cestode: ribbonlike flatworms that are parasitic in the intestines of humans and other vertebrates
taenia: tapeworms parasitic in humans which uses the pig as its intermediate host

Other hyponyms of cestode include echinococcus.

cestode (noun)	taenia (noun)
ribbonlike flatworms that are parasitic in the intestines of humans and other vertebrates	tapeworms parasitic in humans which uses the pig as its intermediate host
	a narrow headband or strip of ribbon worn as a headband