trematode vs platyhelminth

trematode and platyhelminth both are nouns.

Word	Noun	Adjective	Verb	Adverb
trematode	Yes	No	No	No
platyhelminth	Yes	No	No	No

As nouns, platyhelminth is a hypernym of trematode; that is, platyhelminth is a word with a broader meaning than trematode:

trematode: parasitic flatworms having external suckers for attaching to a host
platyhelminth: parasitic or free-living worms having a flattened body

Other hypernyms of trematode include flatworm.

trematode (noun)	platyhelminth (noun)
parasitic flatworms having external suckers for attaching to a host	parasitic or free-living worms having a flattened body