'antioxygenating' is formed in Modern English from the prefix 'anti-' (from Greek 'anti' meaning 'against') + 'oxygen' (from French 'oxygène', ultimately Greek elements 'oxys' meaning 'sharp/acid' and 'genes' meaning 'producer') + the verb-forming suffix '-ate' and the gerund/participle suffix '-ing'.

'antioxygenating' developed from the verb 'antioxygenate' (anti- + oxygen + -ate); 'oxygen' entered English via French 'oxygène' in the late 18th century (coined in scientific French), and the productive English prefix 'anti-' has been used to form compounds meaning 'against' or 'preventing'. The participial form was created by adding '-ing' to the verb.

Originally built from elements meaning 'against oxygen' (anti- + oxygen), the compound has consistently meant 'opposing or preventing oxygenation'; its technical usage has remained specialized (chemistry/biochemistry/materials), so the basic meaning has been largely stable.