: a rudimentary vertebra that lies between the atlas and the occipital bone and that occurs as a regular feature of the structure of reptiles and may occur as an anomaly in humans
Cite this Entry
“Proatlas.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/proatlas. Accessed 31 Oct. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share