'pro-maskers' originates from modern English, combining the prefix 'pro-' (from Latin 'pro' meaning 'for') with 'mask' (from Middle French 'masque') plus the agentive suffix '-er' and plural suffix '-s'.

'mask' changed from Middle French 'masque' (from Italian 'maschera' and ultimately Late Latin 'masca' meaning 'mask, specter') into the English word 'mask'; 'pro-' comes from Latin 'pro' meaning 'for'. The agent suffix '-er' formed 'masker' (one who uses or supports masks), and the plural became 'pro-maskers'.

Initially, 'mask' referred to a disguise or theatrical face covering (and earlier to a specter), but over time it came to commonly mean a protective face covering; combined with 'pro-' the modern term means 'people in favor of masks.'