atlas vertebra vs atlas

atlas vertebra and atlas both are nouns.

Word	Noun	Adjective	Verb	Adverb
atlas vertebra	Yes	No	No	No
atlas	Yes	No	No	No

As nouns, atlas vertebra and atlas are synonyms defined as:

atlas vertebra (noun)	atlas (noun)
the 1st cervical vertebra	a figure of a man used as a supporting column
	the 1st cervical vertebra
	a collection of maps in book form