order Testudinata vs Chelonia

order Testudinata and Chelonia both are nouns.

Word	Noun	Adjective	Verb	Adverb
order Testudinata	Yes	No	No	No
Chelonia	Yes	No	No	No

As nouns, order Testudinata and Chelonia are synonyms defined as:

Other synonyms of order Testudinata include order Chelonia, order Testudines, Testudinata, Testudines.

order Testudinata (noun)	Chelonia (noun)
tortoises and turtles	tortoises and turtles
	green turtles