ectoparasite vs ectozoon

ectoparasite and ectozoon both are nouns.

Word	Noun	Adjective	Verb	Adverb
ectoparasite	Yes	No	No	No
ectozoon	Yes	No	No	No

As nouns, ectoparasite and ectozoon are synonyms defined as:

Other synonyms of ectoparasite include ectozoan, epizoan, epizoon.

ectoparasite (noun)	ectozoon (noun)
any external parasitic organism (as fleas)	any external parasitic organism (as fleas)