'oxygen-poor' originates from the combination of 'oxygen' and 'poor', where 'oxygen' refers to the chemical element essential for respiration, and 'poor' indicates a deficiency or lack.

'oxygen' comes from the French word 'oxygène', coined in the late 18th century, and 'poor' from the Old English 'pōr', meaning lacking or deficient.

Initially, 'oxygen-poor' meant lacking in oxygen, and this meaning has remained consistent in modern usage.