'normoxia' originates from Modern Latin/combining forms: specifically the prefix 'normo-' from Latin 'norma' where 'norma' meant 'rule' or 'standard', and the suffix '-oxia' from Greek 'oxys' via the formation 'oxygen', where 'oxys' originally meant 'sharp' but '-oxia' in modern scientific use denotes relation to oxygen (oxygenation).

'normoxia' was formed in the 20th century by combining the established combining form 'normo-' (from Latin 'norma') with '-oxia' (derived from Greek 'oxys' through the scientific coinage 'oxygen' in the late 18th century), and entered English scientific usage as the term for a normal oxygen condition.

Initially the elements conveyed the sense of 'a standard or normal oxygen condition', and over time this has remained the central meaning: the state of having normal/adequate oxygen.