'atlantal' originates from New Latin, specifically the word 'atlantalis' (formed from 'atlas' + the adjectival suffix '-alis'), where 'atlas' referred to the mythic Titan 'Atlas' (used for the anatomical bone name) and '-alis' meant 'pertaining to'.

'atlantal' changed from Late/Modern Latin 'atlantalis' (or New Latin usage in anatomical terminology) and was adopted into English medical/technical vocabulary as 'atlantal'.

Initially, it meant 'pertaining to Atlas' (in the sense of the mythic figure and the bone named after him), and it evolved to the more specific anatomical meaning 'relating to the atlas (first cervical vertebra, C1)'.