'pneumatize' originates from Greek, specifically the word 'pneuma', where 'pneuma' meant 'breath' or 'air', combined with the formative suffix '-ize' (from Greek/Latin via French) meaning 'to make or to do'.

'pneumatize' changed from the Greek root 'pneuma' into Late Latin/Medieval Latin forms like 'pneumaticus', passed into French/English as 'pneumatic', and the verb form 'pneumatize' was formed in modern English (19th century) to mean 'to make pneumatic or to supply with air'.

Initially it meant 'to provide with breath or air', and over time it evolved into the more technical modern sense 'to make hollow or to provide with air-filled cavities', especially in anatomy and engineering contexts.