'pro-' originates from Latin, specifically the word 'pro', where 'pro-' meant 'for' or 'in favor of'; 'democracy' originates from Greek, specifically the word 'dēmokratia', where 'dēmos' meant 'people' and 'kratos' meant 'power' or 'rule'.

'democracy' changed from Greek 'dēmokratia' into Latin and then Old French/Medieval Latin forms before entering Middle English as 'democracie' and eventually modern English 'democracy'; the compound 'pro-democracy' was formed in modern English (chiefly 20th century) by combining the prefix 'pro-' with 'democracy' to label supporters or movements favoring democratic rule.

Initially the elements literally meant 'for' + 'rule by the people'; over time the compound came to be used specifically to denote support for democratic systems, movements, or policies.