amoeba vs rhizopod

amoeba and rhizopod both are nouns.

Word	Noun	Adjective	Verb	Adverb
amoeba	Yes	No	No	No
rhizopod	Yes	No	No	No

As nouns, rhizopod is a hypernym of amoeba; that is, rhizopod is a word with a broader meaning than amoeba:

amoeba: naked freshwater or marine or parasitic protozoa that form temporary pseudopods for feeding and locomotion
rhizopod: protozoa characterized by a pseudopod

Other hypernyms of amoeba include rhizopodan.

amoeba (noun)	rhizopod (noun)
naked freshwater or marine or parasitic protozoa that form temporary pseudopods for feeding and locomotion	protozoa characterized by a pseudopod