'normoxaemia' originates from Neo-Latin/modern medical formation, combining the prefix 'normo-' (from Latin 'norma' meaning 'rule' or 'standard'), the element 'oxa-' from Greek 'oxys' via 'oxygen' (referring to oxygen), and the suffix '-aemia' from Greek 'haima' meaning 'blood'.

'normoxaemia' was formed in medical English in the late 19th to 20th century by analogy with related terms such as 'anaemia' and 'hypoxaemia' (from 'aemia'/'haemia') and composed with the prefix 'normo-' to indicate 'normal' blood oxygen levels.

Initially coined as a technical compound meaning 'normal blood oxygen', the term's usage has remained specialized and retains this original meaning in modern medical contexts.