spiny-headed worm vs acanthocephalan

spiny-headed worm and acanthocephalan both are nouns.

Word	Noun	Adjective	Verb	Adverb
spiny-headed worm	Yes	No	No	No
acanthocephalan	Yes	No	No	No

As nouns, spiny-headed worm and acanthocephalan are synonyms defined as:

spiny-headed worm and acanthocephalan: any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines

spiny-headed worm (noun)	acanthocephalan (noun)
any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines	any of various worms living parasitically in intestines of vertebrates having a retractile proboscis covered with many hooked spines