'voluntarily' originates from Latin, specifically the word 'voluntarius,' where 'voluntas' meant 'will' or 'desire'. 'Collected' comes from Latin 'collectus,' the past participle of 'colligere,' meaning 'to gather together'.

'voluntarius' transformed into the Old French word 'voluntaire,' and eventually became the modern English word 'voluntary'. 'Collectus' evolved into the Old French 'collecter,' and eventually became the modern English word 'collect'.

Initially, 'voluntarily' meant 'of one's own free will,' and this meaning has largely remained the same in modern usage. 'Collected' initially meant 'gathered together,' which is consistent with its current meaning.