'pro-machine' originates from a combination of the Latin prefix 'pro-' (meaning 'for') and the word 'machine', which comes from Latin 'machina' via Old French 'machine' and ultimately from Greek 'μηχανή' ('mēkhanē') meaning 'device' or 'contrivance'.

'machine' changed from Greek 'μηχανή' to Latin 'machina' and Old French 'machine' before becoming the modern English 'machine'. The prefix 'pro-' comes from Latin 'pro' meaning 'for'; the modern compound 'pro-machine' is formed in contemporary English by joining these elements.

Initially, 'pro-' simply meant 'for' and 'machine' meant 'device' or 'contrivance'; the compounded form has a straightforward, literal meaning—'in favor of machines'—and has not undergone significant semantic shift.