gnathopod vs maxilliped

gnathopod and maxilliped both are nouns.

Word	Noun	Adjective	Verb	Adverb
gnathopod	Yes	No	No	No
maxilliped	Yes	No	No	No

As nouns, gnathopod and maxilliped are synonyms defined as:

gnathopod and maxilliped: One of a set of three paired appendages on the thorax of a decapod crustacean, located just posterior to the maxillae and used in feeding.

gnathopod (noun)	maxilliped (noun)
One of a set of three paired appendages on the thorax of a decapod crustacean, located just posterior to the maxillae and used in feeding.	One of a set of three paired appendages on the thorax of a decapod crustacean, located just posterior to the maxillae and used in feeding.