testacean vs rhizopodan

testacean and rhizopodan both are nouns.

Word	Noun	Adjective	Verb	Adverb
testacean	Yes	No	No	No
rhizopodan	Yes	No	No	No

As nouns, rhizopodan is a hypernym of testacean; that is, rhizopodan is a word with a broader meaning than testacean:

testacean: any of various rhizopods of the order Testacea characterized by having a shell
rhizopodan: protozoa characterized by a pseudopod

Other hypernyms of testacean include rhizopod.

testacean (noun)	rhizopodan (noun)
any of various rhizopods of the order Testacea characterized by having a shell	protozoa characterized by a pseudopod